diff --git a/src/main/java/com/google/cloud/spanner/jdbc/JdbcArray.java b/src/main/java/com/google/cloud/spanner/jdbc/JdbcArray.java
index 1dd83f817..3cb523186 100644
--- a/src/main/java/com/google/cloud/spanner/jdbc/JdbcArray.java
+++ b/src/main/java/com/google/cloud/spanner/jdbc/JdbcArray.java
@@ -92,19 +92,41 @@ private JdbcArray(JdbcDataType type, Object[] elements) throws SQLException {
         this.data =
             java.lang.reflect.Array.newInstance(
                 elements.getClass().getComponentType(), elements.length);
+        System.arraycopy(elements, 0, this.data, 0, elements.length);
+      } else if (type == JdbcDataType.INT64 && requiresWideningToLong(elements)) {
+        // Convert Byte[], Short[], and Integer[] to Long[] for INT64 type
+        // since Spanner only supports ARRAY<INT64>
+        this.data = convertToLongArray(elements);
       } else {
         this.data = java.lang.reflect.Array.newInstance(type.getJavaClass(), elements.length);
+        try {
+          System.arraycopy(elements, 0, this.data, 0, elements.length);
+        } catch (Exception e) {
+          throw JdbcSqlExceptionFactory.of(
+              "Could not copy array elements. Make sure the supplied array only contains elements of class "
+                  + type.getJavaClass().getName(),
+              Code.UNKNOWN,
+              e);
+        }
       }
-      try {
-        System.arraycopy(elements, 0, this.data, 0, elements.length);
-      } catch (Exception e) {
-        throw JdbcSqlExceptionFactory.of(
-            "Could not copy array elements. Make sure the supplied array only contains elements of class "
-                + type.getJavaClass().getName(),
-            Code.UNKNOWN,
-            e);
+    }
+  }
+
+  private static boolean requiresWideningToLong(Object[] elements) {
+    Class<?> componentType = elements.getClass().getComponentType();
+    return componentType == Byte.class
+        || componentType == Short.class
+        || componentType == Integer.class;
+  }
+
+  private static Long[] convertToLongArray(Object[] elements) {
+    Long[] longElements = new Long[elements.length];
+    for (int i = 0; i < elements.length; i++) {
+      if (elements[i] != null) {
+        longElements[i] = ((Number) elements[i]).longValue();
       }
     }
+    return longElements;
   }
 
   private JdbcArray(JdbcDataType type, List<?> elements) {
diff --git a/src/main/java/com/google/cloud/spanner/jdbc/JdbcDataType.java b/src/main/java/com/google/cloud/spanner/jdbc/JdbcDataType.java
index bb2f7c007..892c0057c 100644
--- a/src/main/java/com/google/cloud/spanner/jdbc/JdbcDataType.java
+++ b/src/main/java/com/google/cloud/spanner/jdbc/JdbcDataType.java
@@ -201,7 +201,7 @@ public Set<String> getPostgreSQLAliases() {
   },
   INT64 {
     private final Set<Class<?>> classes =
-        new HashSet<>(Arrays.asList(Byte.class, Integer.class, Long.class));
+        new HashSet<>(Arrays.asList(Byte.class, Short.class, Integer.class, Long.class));
 
     @Override
     public int getSqlType() {
diff --git a/src/main/java/com/google/cloud/spanner/jdbc/JdbcParameterStore.java b/src/main/java/com/google/cloud/spanner/jdbc/JdbcParameterStore.java
index 0964db087..b43b44ddc 100644
--- a/src/main/java/com/google/cloud/spanner/jdbc/JdbcParameterStore.java
+++ b/src/main/java/com/google/cloud/spanner/jdbc/JdbcParameterStore.java
@@ -875,6 +875,8 @@ private Builder setArrayValue(ValueBinder<Builder> binder, int type, Object valu
       return binder.toBoolArray((boolean[]) value);
     } else if (Boolean[].class.isAssignableFrom(value.getClass())) {
       return binder.toBoolArray(Arrays.asList((Boolean[]) value));
+    } else if (Byte[].class.isAssignableFrom(value.getClass())) {
+      return binder.toInt64Array(toLongList((Byte[]) value));
     } else if (short[].class.isAssignableFrom(value.getClass())) {
       long[] l = new long[((short[]) value).length];
       for (int i = 0; i < l.length; i++) {
diff --git a/src/test/java/com/google/cloud/spanner/jdbc/JdbcArrayTest.java b/src/test/java/com/google/cloud/spanner/jdbc/JdbcArrayTest.java
index bfae4e556..44dd1a78f 100644
--- a/src/test/java/com/google/cloud/spanner/jdbc/JdbcArrayTest.java
+++ b/src/test/java/com/google/cloud/spanner/jdbc/JdbcArrayTest.java
@@ -144,6 +144,82 @@ public void testCreateArrayTypeName() throws SQLException {
       assertThat(rs.next()).isFalse();
     }
 
+    // Test that Byte[] arrays are automatically widened to Long[] for INT64 type
+    Long[] data;
+    array = JdbcArray.createArray("INT64", new Byte[] {1, 2, 3, null, Byte.MAX_VALUE});
+    assertThat(array.getBaseType()).isEqualTo(Types.BIGINT);
+    // Data should be stored as Long[]
+    assertThat(array.getArray()).isInstanceOf(Long[].class);
+    data = (Long[]) array.getArray();
+    assertThat(data[0]).isEqualTo(1L);
+    assertThat(data[1]).isEqualTo(2L);
+    assertThat(data[2]).isEqualTo(3L);
+    assertThat(data[3]).isNull();
+    assertThat(data[4]).isEqualTo((long) Byte.MAX_VALUE);
+
+    try (ResultSet rs = array.getResultSet()) {
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getByte(2)).isEqualTo((byte) 1);
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getByte(2)).isEqualTo((byte) 2);
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getByte(2)).isEqualTo((byte) 3);
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getByte(2)).isEqualTo((byte) 0);
+      assertTrue(rs.wasNull());
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getByte(2)).isEqualTo(Byte.MAX_VALUE);
+      assertThat(rs.next()).isFalse();
+    }
+
+    // Test that Short[] arrays are automatically widened to Long[] for INT64 type
+    array = JdbcArray.createArray("INT64", new Short[] {100, 200, null, Short.MAX_VALUE});
+    assertThat(array.getBaseType()).isEqualTo(Types.BIGINT);
+    // Data should be stored as Long[]
+    assertThat(array.getArray()).isInstanceOf(Long[].class);
+    data = (Long[]) array.getArray();
+    assertThat(data[0]).isEqualTo(100L);
+    assertThat(data[1]).isEqualTo(200L);
+    assertThat(data[2]).isNull();
+    assertThat(data[3]).isEqualTo((long) Short.MAX_VALUE);
+
+    try (ResultSet rs = array.getResultSet()) {
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getShort(2)).isEqualTo((short) 100);
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getShort(2)).isEqualTo((short) 200);
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getShort(2)).isEqualTo((short) 0);
+      assertTrue(rs.wasNull());
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getShort(2)).isEqualTo(Short.MAX_VALUE);
+      assertThat(rs.next()).isFalse();
+    }
+
+    // Test that Integer[] arrays are automatically widened to Long[] for INT64 type
+    array = JdbcArray.createArray("INT64", new Integer[] {1000, 2000, null, Integer.MAX_VALUE});
+    assertThat(array.getBaseType()).isEqualTo(Types.BIGINT);
+    // Data should be stored as Long[]
+    assertThat(array.getArray()).isInstanceOf(Long[].class);
+    data = (Long[]) array.getArray();
+    assertThat(data[0]).isEqualTo(1000L);
+    assertThat(data[1]).isEqualTo(2000L);
+    assertThat(data[2]).isNull();
+    assertThat(data[3]).isEqualTo((long) Integer.MAX_VALUE);
+
+    try (ResultSet rs = array.getResultSet()) {
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getInt(2)).isEqualTo(1000);
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getInt(2)).isEqualTo(2000);
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getInt(2)).isEqualTo(0);
+      assertTrue(rs.wasNull());
+      assertThat(rs.next()).isTrue();
+      assertThat(rs.getInt(2)).isEqualTo(Integer.MAX_VALUE);
+      assertThat(rs.next()).isFalse();
+    }
+
     array =
         JdbcArray.createArray("NUMERIC", new BigDecimal[] {BigDecimal.ONE, null, BigDecimal.TEN});
     assertThat(array.getBaseType()).isEqualTo(Types.NUMERIC);