diff --git a/depends/packages/bdb.mk b/depends/packages/bdb.mk
index 6c9876c2c7c..3cd2e28858e 100644
--- a/depends/packages/bdb.mk
+++ b/depends/packages/bdb.mk
@@ -10,6 +10,7 @@ $(package)_config_opts=--disable-shared --enable-cxx --disable-replication
 $(package)_config_opts_mingw32=--enable-mingw
 $(package)_config_opts_linux=--with-pic
 $(package)_cxxflags=-std=c++11
+$(package)_cppflags_mingw32=-DUNICODE -D_UNICODE
 endef
 
 define $(package)_preprocess_cmds