diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index 453ccd9..23f5f82 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -67,13 +67,13 @@
 #	Ruby interface:
 #	  RUBY=[Path to Ruby directory]
 #	  DYNAMIC_RUBY=yes (to load the Ruby DLL dynamically)
-#	  RUBY_VER=[Ruby version, eg 18, 19, 20] (default is 18)
-#	  RUBY_VER_LONG=[Ruby version, eg 1.8, 1.9.1, 2.0.0] (default is 1.8)
-#	    You must set RUBY_VER_LONG when change RUBY_VER.
-#	    RUBY_API_VER is derived from RUBY_VER_LONG.
+#	  RUBY_VER=[Ruby version, eg 19, 22] (default is 22)
+#	  RUBY_API_VER_LONG=[Ruby API version, eg 1.8, 1.9.1, 2.2.0]
+#	  		    (default is 2.2.0)
+#	    You must set RUBY_API_VER_LONG when change RUBY_VER.
 #	    Note: If you use Ruby 1.9.3, set as follows:
 #	      RUBY_VER=19
-#	      RUBY_VER_LONG=1.9.1 (not 1.9.3, because the API version is 1.9.1.)
+#	      RUBY_API_VER_LONG=1.9.1 (not 1.9.3, because the API version is 1.9.1.)
 #
 #	Tcl interface:
 #	  TCL=[Path to Tcl directory]
@@ -917,13 +917,16 @@
 !ifdef RUBY
 #  Set default value
 !ifndef RUBY_VER
-RUBY_VER = 18
+RUBY_VER = 22
 !endif
 !ifndef RUBY_VER_LONG
-RUBY_VER_LONG = 1.8
+RUBY_VER_LONG = 2.2.0
+!endif
+!ifndef RUBY_API_VER_LONG
+RUBY_API_VER_LONG = $(RUBY_VER_LONG)
 !endif
 !ifndef RUBY_API_VER
-RUBY_API_VER = $(RUBY_VER_LONG:.=)
+RUBY_API_VER = $(RUBY_API_VER_LONG:.=)
 !endif
 
 !if $(RUBY_VER) >= 18
@@ -966,9 +969,9 @@
 CFLAGS = $(CFLAGS) -DFEAT_RUBY
 RUBY_OBJ = $(OUTDIR)\if_ruby.obj
 !if $(RUBY_VER) >= 19
-RUBY_INC = /I "$(RUBY)\lib\ruby\$(RUBY_VER_LONG)\$(RUBY_PLATFORM)" /I "$(RUBY)\include\ruby-$(RUBY_VER_LONG)" /I "$(RUBY)\include\ruby-$(RUBY_VER_LONG)\$(RUBY_PLATFORM)"
+RUBY_INC = /I "$(RUBY)\lib\ruby\$(RUBY_API_VER_LONG)\$(RUBY_PLATFORM)" /I "$(RUBY)\include\ruby-$(RUBY_API_VER_LONG)" /I "$(RUBY)\include\ruby-$(RUBY_API_VER_LONG)\$(RUBY_PLATFORM)"
 !else
-RUBY_INC = /I "$(RUBY)\lib\ruby\$(RUBY_VER_LONG)\$(RUBY_PLATFORM)"
+RUBY_INC = /I "$(RUBY)\lib\ruby\$(RUBY_API_VER_LONG)\$(RUBY_PLATFORM)"
 !endif
 RUBY_LIB = $(RUBY)\lib\$(RUBY_INSTALL_NAME).lib
 # Do we want to load Ruby dynamically?