diff --git a/src/github.com/matrix-org/dendrite/mediaapi/writers/upload.go b/src/github.com/matrix-org/dendrite/mediaapi/writers/upload.go
index 7b6b4876d..363722e8a 100644
--- a/src/github.com/matrix-org/dendrite/mediaapi/writers/upload.go
+++ b/src/github.com/matrix-org/dendrite/mediaapi/writers/upload.go
@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/url"
 	"os"
 	"path"
 	"strings"
@@ -127,12 +128,16 @@ func Upload(req *http.Request, cfg config.MediaAPI, db *storage.Database) util.J
 		},
 	}
 
-	// FIXME: if no Content-Disposition then set
-
 	if resErr = r.Validate(cfg.MaxFileSize); resErr != nil {
 		return *resErr
 	}
 
+	if len(r.MediaMetadata.UploadName) > 0 {
+		r.MediaMetadata.ContentDisposition = types.ContentDisposition(
+			"inline; filename*=utf-8''" + url.PathEscape(string(r.MediaMetadata.UploadName)),
+		)
+	}
+
 	logger.WithFields(log.Fields{
 		"Origin":              r.MediaMetadata.Origin,
 		"UploadName":          r.MediaMetadata.UploadName,