diff --git a/src/sync.cpp b/src/sync.cpp
index e641716eb8..d57bd79e7e 100644
--- a/src/sync.cpp
+++ b/src/sync.cpp
@@ -13,8 +13,6 @@
 #include <util/strencodings.h>
 #include <util/threadnames.h>
 
-#include <boost/thread/mutex.hpp>
-
 #include <map>
 #include <mutex>
 #include <set>
@@ -225,7 +223,6 @@ template void EnterCritical(const char*, const char*, int, Mutex*, bool);
 template void EnterCritical(const char*, const char*, int, RecursiveMutex*, bool);
 template void EnterCritical(const char*, const char*, int, std::mutex*, bool);
 template void EnterCritical(const char*, const char*, int, std::recursive_mutex*, bool);
-template void EnterCritical(const char*, const char*, int, boost::mutex*, bool);
 
 void CheckLastCritical(void* cs, std::string& lockname, const char* guardname, const char* file, int line)
 {
diff --git a/src/test/sync_tests.cpp b/src/test/sync_tests.cpp
index bc14213ae8..25fca556a7 100644
--- a/src/test/sync_tests.cpp
+++ b/src/test/sync_tests.cpp
@@ -6,7 +6,6 @@
 #include <test/util/setup_common.h>
 
 #include <boost/test/unit_test.hpp>
-#include <boost/thread/mutex.hpp>
 
 #include <mutex>
 
@@ -136,11 +135,6 @@ BOOST_AUTO_TEST_CASE(double_lock_mutex)
     TestDoubleLock<Mutex>(true /* should throw */);
 }
 
-BOOST_AUTO_TEST_CASE(double_lock_boost_mutex)
-{
-    TestDoubleLock<boost::mutex>(true /* should throw */);
-}
-
 BOOST_AUTO_TEST_CASE(double_lock_recursive_mutex)
 {
     TestDoubleLock<RecursiveMutex>(false /* should not throw */);