diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 872aad6b046..3475a9d52c6 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -5888,8 +5888,17 @@ namespace ts {
             Debug.assert(!!(left.flags & TypeFlags.Object) && !!(right.flags & TypeFlags.Object), "Only object types may be spread.");
             const members = createMap<Symbol>();
             const skippedPrivateMembers = createMap<boolean>();
-            const stringIndexInfo = unionSpreadIndexInfos(getIndexInfoOfType(left, IndexKind.String), getIndexInfoOfType(right, IndexKind.String));
-            const numberIndexInfo = unionSpreadIndexInfos(getIndexInfoOfType(left, IndexKind.Number), getIndexInfoOfType(right, IndexKind.Number));
+            let stringIndexInfo: IndexInfo;
+            let numberIndexInfo: IndexInfo;
+            if (left === emptyObjectType) {
+                // for the first spread element, left === emptyObjectType, so take the right's string indexer
+                stringIndexInfo = getIndexInfoOfType(right, IndexKind.String);
+                numberIndexInfo = getIndexInfoOfType(right, IndexKind.Number);
+            }
+            else {
+                stringIndexInfo = unionSpreadIndexInfos(getIndexInfoOfType(left, IndexKind.String), getIndexInfoOfType(right, IndexKind.String));
+                numberIndexInfo = unionSpreadIndexInfos(getIndexInfoOfType(left, IndexKind.Number), getIndexInfoOfType(right, IndexKind.Number));
+            }
 
             const isFromSpread = right.symbol !== symbol;
             for (const rightProp of getPropertiesOfType(right)) {