diff --git src/wp-admin/includes/ajax-actions.php src/wp-admin/includes/ajax-actions.php
index 40f8f5d..ebda65c 100644
--- src/wp-admin/includes/ajax-actions.php
+++ src/wp-admin/includes/ajax-actions.php
@@ -2454,6 +2454,16 @@ function wp_ajax_send_attachment_to_editor() {
 
 		$title = ''; // We no longer insert title tags into <img> tags, as they are redundant.
 		$html = get_image_send_to_editor( $id, $caption, $title, $align, $url, (bool) $rel, $size, $alt );
+
+		// 'src' attribute should not be HTTPS if the site URL is not also HTTPS.
+		if ( is_ssl() ) {
+			$upload_dir = wp_upload_dir();
+			if ( 'https' !== substr( $upload_dir['basedir'], 0, 5 ) ) {
+				if ( preg_match( '|src\=\"([^"]*)\"|', $html, $matches ) ) {
+					$html = str_replace( $matches[1], set_url_scheme( $matches[1], 'http' ), $html );
+				}
+			}
+		}
 	} elseif ( wp_attachment_is( 'video', $post ) || wp_attachment_is( 'audio', $post )  ) {
 		$html = stripslashes_deep( $_POST['html'] );
 	}
diff --git tests/phpunit/includes/testcase-ajax.php tests/phpunit/includes/testcase-ajax.php
index b415976..0a532bb 100644
--- tests/phpunit/includes/testcase-ajax.php
+++ tests/phpunit/includes/testcase-ajax.php
@@ -46,7 +46,7 @@ abstract class WP_Ajax_UnitTestCase extends WP_UnitTestCase {
 		'hidden-columns', 'update-welcome-panel', 'menu-get-metabox', 'wp-link-ajax',
 		'menu-locations-save', 'menu-quick-search', 'meta-box-order', 'get-permalink',
 		'sample-permalink', 'inline-save', 'inline-save-tax', 'find_posts', 'widgets-order',
-		'save-widget', 'set-post-thumbnail', 'date_format', 'time_format', 'wp-fullscreen-save-post',
+		'save-widget', 'send-attachment-to-editor', 'set-post-thumbnail', 'date_format', 'time_format', 'wp-fullscreen-save-post',
 		'wp-remove-post-lock', 'dismiss-wp-pointer', 'heartbeat', 'nopriv_heartbeat',
 	);
 
diff --git tests/phpunit/tests/ajax/SendAttachmentToEditor.php tests/phpunit/tests/ajax/SendAttachmentToEditor.php
new file mode 100644
index 0000000..e7b77cd
--- /dev/null
+++ tests/phpunit/tests/ajax/SendAttachmentToEditor.php
@@ -0,0 +1,111 @@
+<?php
+
+/**
+ * Admin ajax functions to be tested
+ */
+require_once( ABSPATH . 'wp-admin/includes/ajax-actions.php' );
+
+/**
+ * @group ajax
+ */
+class Tests_Ajax_SendAttachmentToEditor extends WP_Ajax_UnitTestCase {
+	private $_ids;
+
+	/**
+	 * Set up the test fixture
+	 */
+	public function setUp() {
+		parent::setUp();
+		$_SERVER['REMOTE_ADDR'] = '';
+	}
+
+	/**
+	 * Tear down the test fixture.
+	 */
+	public function tearDown() {
+		// Cleanup
+		foreach ( $this->_ids as $id ) {
+			wp_delete_attachment( $id, true );
+		}
+
+		parent::tearDown();
+	}
+
+	/**
+	 * @ticket 32112
+	 */
+	public function test_src_should_be_http_when_homeurl_is_http_even_when_is_ssl() {
+		$_https = isset( $_SERVER['HTTPS'] ) ? $_SERVER['HTTPS'] : null;
+		$_post_backup = $_POST;
+
+		$post_id = $this->factory->post->create();
+
+		$filename = DIR_TESTDATA . '/images/canola.jpg';
+		$contents = file_get_contents( $filename );
+
+		$upload = wp_upload_bits( basename( $filename ), null, $contents );
+		$attachment_id = $this->_make_attachment( $upload, $post_id );
+
+		$attachment_url = wp_get_attachment_url( $attachment_id );
+		$this->assertSame( $attachment_url, set_url_scheme( $attachment_url, 'http' ) );
+
+		wp_set_current_user( $this->factory->user->create( array( 'role' => 'editor' ) ) );
+
+		// Fake SSL.
+		$_SERVER['HTTPS'] = 'on';
+
+		// Set up a default request.
+		$_POST['nonce'] = wp_create_nonce( 'media-send-to-editor' );
+		$_POST['attachment'] = array(
+			'id' => $attachment_id,
+		);
+		$_POST['post_id'] = $post_id;
+
+		// Make the request
+		try {
+			$this->_handleAjax( 'send-attachment-to-editor' );
+		} catch ( WPAjaxDieContinueException $e ) {
+			unset( $e );
+		}
+
+		// Clean up before assertion.
+		if ( is_null( $_https ) ) {
+			unset( $_SERVER['HTTPS'] );
+		} else {
+			$_SERVER['HTTPS'] = $_https;
+		}
+
+		$_POST = $_post_backup;
+
+		$response = json_decode( $this->_last_response );
+
+		// We don't test against the full attachment URL because of resizing, etc.
+		$attachment_base = substr( $attachment_url, 0, strrpos( $attachment_url, '/' ) );
+		$this->assertContains( 'src="' . $attachment_base, $response->data );
+	}
+
+	private function _make_attachment( $upload, $parent_post_id = 0 ) {
+		$type = '';
+		if ( !empty($upload['type']) ) {
+			$type = $upload['type'];
+		} else {
+			$mime = wp_check_filetype( $upload['file'] );
+			if ($mime)
+				$type = $mime['type'];
+		}
+
+		$attachment = array(
+			'post_title' => basename( $upload['file'] ),
+			'post_content' => '',
+			'post_type' => 'attachment',
+			'post_parent' => $parent_post_id,
+			'post_mime_type' => $type,
+			'guid' => $upload[ 'url' ],
+		);
+
+		// Save the data
+		$id = wp_insert_attachment( $attachment, $upload[ 'file' ], $parent_post_id );
+		wp_update_attachment_metadata( $id, wp_generate_attachment_metadata( $id, $upload['file'] ) );
+		return $this->_ids[] = $id;
+	}
+}