diff --git a/test/ruby/test_dir_m17n.rb b/test/ruby/test_dir_m17n.rb
index 5d009aceb1..acfee815c7 100644
--- a/test/ruby/test_dir_m17n.rb
+++ b/test/ruby/test_dir_m17n.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: false
 require 'test/unit'
 require 'tmpdir'
+require '-test-/file'
 
 class TestDir_M17N < Test::Unit::TestCase
   def with_tmpdir
@@ -59,6 +60,8 @@ class TestDir_M17N < Test::Unit::TestCase
 
   def test_filename_extutf8_invalid
     return if /cygwin/ =~ RUBY_PLATFORM
+    # High Sierra's APFS cannot use invalid filenames
+    return if Bug::File::Fs.fsname(Dir.tmpdir) == "apfs"
     with_tmpdir {|d|
       assert_separately(%w[-EASCII-8BIT], <<-'EOS', :chdir=>d)
         filename = "\xff".force_encoding("ASCII-8BIT") # invalid byte sequence as UTF-8
@@ -375,7 +378,12 @@ class TestDir_M17N < Test::Unit::TestCase
       a = "file_one*".force_encoding Encoding::IBM437
       b = "file_two*".force_encoding Encoding::EUC_JP
       assert_equal([a, b].map(&:encoding), Dir[a, b].map(&:encoding))
-      dir = "\u{76EE 5F551}"
+      if Bug::File::Fs.fsname(Dir.pwd) == "apfs"
+        # High Sierra's APFS cannot use filenames with undefined character
+        dir = "\u{76EE}"
+      else
+        dir = "\u{76EE 5F551}"
+      end
       Dir.mkdir(dir)
       list << dir
       bug12081 = '[ruby-core:73868] [Bug #12081]'
diff --git a/test/ruby/test_file_exhaustive.rb b/test/ruby/test_file_exhaustive.rb
index f3845f7f51..5be36063c4 100644
--- a/test/ruby/test_file_exhaustive.rb
+++ b/test/ruby/test_file_exhaustive.rb
@@ -3,6 +3,7 @@ require "test/unit"
 require "fileutils"
 require "tmpdir"
 require "socket"
+require '-test-/file'
 
 class TestFileExhaustive < Test::Unit::TestCase
   DRIVE = Dir.pwd[%r'\A(?:[a-z]:|//[^/]+/[^/]+)'i]
@@ -572,7 +573,13 @@ class TestFileExhaustive < Test::Unit::TestCase
       t2 = File.open(file) {|f| f.atime}
       assert_kind_of(Time, t1)
       assert_kind_of(Time, t2)
-      assert_equal(t1, t2)
+      # High Sierra's APFS can handle nano-sec precise.
+      # t1 value is difference from t2 on APFS.
+      if Bug::File::Fs.fsname(Dir.tmpdir) == "apfs"
+        assert_equal(t1.to_i, t2.to_i)
+      else
+        assert_equal(t1, t2)
+      end
     end
     assert_raise(Errno::ENOENT) { File.atime(nofile) }
   end
@@ -749,6 +756,8 @@ class TestFileExhaustive < Test::Unit::TestCase
         begin
           open(file) {}
         rescue
+          # High Sierra's APFS cannot use filenames with undefined character
+          next if Bug::File::Fs.fsname(Dir.tmpdir) == "apfs"
           assert_equal(file, full_path, mesg)
         else
           assert_equal(regular_file, full_path, mesg)
diff --git a/version.h b/version.h
index b3eae32db1..f10aa53bc4 100644
--- a/version.h
+++ b/version.h
@@ -1,6 +1,6 @@
 #define RUBY_VERSION "2.4.4"
 #define RUBY_RELEASE_DATE "2018-03-04"
-#define RUBY_PATCHLEVEL 247
+#define RUBY_PATCHLEVEL 248
 
 #define RUBY_RELEASE_YEAR 2018
 #define RUBY_RELEASE_MONTH 3