diff --git a/auto/cc/msvc b/auto/cc/msvc
index d4c0be4c3..567bac7bc 100644
--- a/auto/cc/msvc
+++ b/auto/cc/msvc
@@ -22,6 +22,21 @@ have=NGX_COMPILER value="\"cl $NGX_MSVC_VER\"" . auto/define
 ngx_msvc_ver=`echo $NGX_MSVC_VER | sed -e 's/^\([0-9]*\).*/\1/'`
 
 
+# detect x64 builds
+
+case "$NGX_MSVC_VER" in
+
+    *x64)
+        NGX_MACHINE=amd64
+    ;;
+
+    *)
+        NGX_MACHINE=i386
+    ;;
+
+esac
+
+
 # optimizations
 
 # maximize speed, equivalent to -Og -Oi -Ot -Oy -Ob2 -Gs -GF -Gy
diff --git a/auto/lib/openssl/make b/auto/lib/openssl/make
index 126a23875..a7e9369e7 100644
--- a/auto/lib/openssl/make
+++ b/auto/lib/openssl/make
@@ -7,11 +7,24 @@ case "$CC" in
 
     cl)
 
+        case "$NGX_MACHINE" in
+
+            amd64)
+                OPENSSL_TARGET=VC-WIN64A
+            ;;
+
+            *)
+                OPENSSL_TARGET=VC-WIN32
+            ;;
+
+        esac
+
         cat << END                                            >> $NGX_MAKEFILE
 
 $OPENSSL/openssl/include/openssl/ssl.h:	$NGX_MAKEFILE
 	\$(MAKE) -f auto/lib/openssl/makefile.msvc			\
-		OPENSSL="$OPENSSL" OPENSSL_OPT="$OPENSSL_OPT"
+		OPENSSL="$OPENSSL" OPENSSL_OPT="$OPENSSL_OPT"		\
+		OPENSSL_TARGET="$OPENSSL_TARGET"
 
 END
 
diff --git a/auto/lib/openssl/makefile.msvc b/auto/lib/openssl/makefile.msvc
index a30b28669..ed17cde08 100644
--- a/auto/lib/openssl/makefile.msvc
+++ b/auto/lib/openssl/makefile.msvc
@@ -6,7 +6,7 @@
 all:
 	cd $(OPENSSL)
 
-	perl Configure VC-WIN32 no-shared no-threads			\
+	perl Configure $(OPENSSL_TARGET) no-shared no-threads		\
 		--prefix="%cd%/openssl" 				\
 		--openssldir="%cd%/openssl/ssl" 			\
 		$(OPENSSL_OPT)