diff --git a/src/qt/walletmodel.cpp b/src/qt/walletmodel.cpp
index 6f3e3b0aa..14f29c933 100644
--- a/src/qt/walletmodel.cpp
+++ b/src/qt/walletmodel.cpp
@@ -488,6 +488,7 @@ bool WalletModel::getPubKey(const CKeyID &address, CPubKey& vchPubKeyOut) const
 // returns a list of COutputs from COutPoints
 void WalletModel::getOutputs(const std::vector<COutPoint>& vOutpoints, std::vector<COutput>& vOutputs)
 {
+    LOCK(wallet->cs_wallet);
     BOOST_FOREACH(const COutPoint& outpoint, vOutpoints)
     {
         if (!wallet->mapWallet.count(outpoint.hash)) continue;