diff --git a/.changelog/19944.txt b/.changelog/19944.txt
new file mode 100644
index 00000000000..c75c04dbb42
--- /dev/null
+++ b/.changelog/19944.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+data-source/aws_kms_public_key: Correctly base64 encode `public_key` value
+```
\ No newline at end of file
diff --git a/aws/data_source_aws_kms_public_key.go b/aws/data_source_aws_kms_public_key.go
index 427564302c6..13d5391df68 100644
--- a/aws/data_source_aws_kms_public_key.go
+++ b/aws/data_source_aws_kms_public_key.go
@@ -1,6 +1,7 @@
 package aws
 
 import (
+	"encoding/base64"
 	"fmt"
 
 	"github.com/aws/aws-sdk-go/aws"
@@ -75,7 +76,7 @@ func dataSourceAwsKmsPublicKeyRead(d *schema.ResourceData, meta interface{}) err
 	d.Set("arn", output.KeyId)
 	d.Set("customer_master_key_spec", output.CustomerMasterKeySpec)
 	d.Set("key_usage", output.KeyUsage)
-	d.Set("public_key", string(output.PublicKey))
+	d.Set("public_key", base64.StdEncoding.EncodeToString(output.PublicKey))
 
 	if err := d.Set("encryption_algorithms", flattenStringList(output.EncryptionAlgorithms)); err != nil {
 		return fmt.Errorf("error setting encryption_algorithms: %w", err)