diff --git a/src/chain.cpp b/src/chain.cpp
index 719256106e08f..f2573c6d4829d 100644
--- a/src/chain.cpp
+++ b/src/chain.cpp
@@ -82,9 +82,10 @@ CBlockIndex* CBlockIndex::GetAncestor(int height)
     while (heightWalk > height) {
         int heightSkip = GetSkipHeight(heightWalk);
         int heightSkipPrev = GetSkipHeight(heightWalk - 1);
-        if (heightSkip == height ||
-            (heightSkip > height && !(heightSkipPrev < heightSkip - 2 &&
-                                      heightSkipPrev >= height))) {
+         if (pindexWalk->pskip != NULL &&
+             (heightSkip == height ||
+              (heightSkip > height && !(heightSkipPrev < heightSkip - 2 &&
+                                        heightSkipPrev >= height)))) {
             // Only follow pskip if pprev->pskip isn't better than pskip->pprev.
             pindexWalk = pindexWalk->pskip;
             heightWalk = heightSkip;