diff --git a/lib/template-parts.php b/lib/template-parts.php
index 464200f66d000a..da1407ed667e07 100644
--- a/lib/template-parts.php
+++ b/lib/template-parts.php
@@ -138,7 +138,7 @@ function filter_rest_wp_template_part_query( $args, $request ) {
 		$tax_query   = isset( $args['tax_query'] ) ? $args['tax_query'] : array();
 		$tax_query[] = array(
 			'taxonomy' => 'wp_theme',
-			'field'    => 'slug',
+			'field'    => 'name',
 			'terms'    => $request['theme'],
 		);
 
diff --git a/packages/block-library/src/template-part/edit/use-template-part-post.js b/packages/block-library/src/template-part/edit/use-template-part-post.js
index fed17e7a4cd77a..5546e6ca7f0172 100644
--- a/packages/block-library/src/template-part/edit/use-template-part-post.js
+++ b/packages/block-library/src/template-part/edit/use-template-part-post.js
@@ -23,6 +23,8 @@ export default function useTemplatePartPost( postId, slug, theme ) {
 			// load the auto-draft created from the
 			// relevant file.
 			if ( slug && theme ) {
+				const currentTheme = select( 'core' ).getCurrentTheme()
+					?.stylesheet;
 				const cleanedSlug = cleanForSlug( slug );
 				const posts = select( 'core' ).getEntityRecords(
 					'postType',
@@ -30,7 +32,7 @@ export default function useTemplatePartPost( postId, slug, theme ) {
 					{
 						status: [ 'publish', 'auto-draft' ],
 						slug: cleanedSlug,
-						theme,
+						theme: currentTheme,
 					}
 				);
 
diff --git a/packages/block-library/src/template-part/index.php b/packages/block-library/src/template-part/index.php
index a960aa969bc906..313ef8a85d319b 100644
--- a/packages/block-library/src/template-part/index.php
+++ b/packages/block-library/src/template-part/index.php
@@ -28,7 +28,7 @@ function render_block_core_template_part( $attributes ) {
 				'tax_query'      => array(
 					array(
 						'taxonomy' => 'wp_theme',
-						'field'    => 'slug',
+						'field'    => 'name',
 						'terms'    => $attributes['theme'],
 					),
 				),