diff --git a/ext/zlib/zlib.c b/ext/zlib/zlib.c
index f13ef4d..0a8f5e8 100644
--- a/ext/zlib/zlib.c
+++ b/ext/zlib/zlib.c
@@ -1368,6 +1368,14 @@ get_zstream(VALUE obj)
     return z;
 }
 
+static void
+zstream_check_reinitialize(VALUE obj, struct zstream *z)
+{
+    if (ZSTREAM_IS_READY(z)) {
+	rb_raise(rb_eRuntimeError, "reinitializing %"PRIsVALUE, rb_obj_class(obj));
+    }
+}
+
 
 /* ------------------------------------------------------------------------- */
 
@@ -1714,6 +1722,7 @@ rb_deflate_initialize(int argc, VALUE *argv, VALUE obj)
 
     rb_scan_args(argc, argv, "04", &level, &wbits, &memlevel, &strategy);
     TypedData_Get_Struct(obj, struct zstream, &zstream_data_type, z);
+    zstream_check_reinitialize(obj, z);
 
     err = deflateInit2(&z->stream, ARG_LEVEL(level), Z_DEFLATED,
 		       ARG_WBITS(wbits), ARG_MEMLEVEL(memlevel),
@@ -2070,6 +2079,7 @@ rb_inflate_initialize(int argc, VALUE *argv, VALUE obj)
 
     rb_scan_args(argc, argv, "01", &wbits);
     TypedData_Get_Struct(obj, struct zstream, &zstream_data_type, z);
+    zstream_check_reinitialize(obj, z);
 
     err = inflateInit2(&z->stream, ARG_WBITS(wbits));
     if (err != Z_OK) {
@@ -3805,6 +3815,7 @@ rb_gzwriter_initialize(int argc, VALUE *argv, VALUE obj)
 
     rb_scan_args(argc, argv, "12", &io, &level, &strategy);
     TypedData_Get_Struct(obj, struct gzfile, &gzfile_data_type, gz);
+    zstream_check_reinitialize(obj, &gz->z);
 
     /* this is undocumented feature of zlib */
     gz->level = ARG_LEVEL(level);
@@ -4067,6 +4078,7 @@ rb_gzreader_initialize(int argc, VALUE *argv, VALUE obj)
     int err;
 
     TypedData_Get_Struct(obj, struct gzfile, &gzfile_data_type, gz);
+    zstream_check_reinitialize(obj, &gz->z);
     rb_scan_args(argc, argv, "1:", &io, &opt);
 
     /* this is undocumented feature of zlib */
diff --git a/test/zlib/test_zlib.rb b/test/zlib/test_zlib.rb
index e1ecbf8..693bbce 100644
--- a/test/zlib/test_zlib.rb
+++ b/test/zlib/test_zlib.rb
@@ -1558,6 +1558,21 @@ def ary.write(*args)
   end
 
   class TestZlib < Test::Unit::TestCase
+    def test_reinitialize
+      z = Zlib::Deflate.new
+      assert_raise(RuntimeError) { z.send(:initialize) }
+      z.close
+      z = Zlib::Inflate.new
+      assert_raise(RuntimeError) { z.send(:initialize) }
+      z.close
+      gz = Zlib::GzipWriter.new(StringIO.new(+""))
+      assert_raise(RuntimeError) { gz.send(:initialize, StringIO.new(+"")) }
+      gz.close
+      gz = Zlib::GzipReader.new(StringIO.new(Zlib.gzip("foo")))
+      assert_raise(RuntimeError) { gz.send(:initialize, StringIO.new(Zlib.gzip("foo"))) }
+      gz.close
+    end
+
     def test_version
       assert_instance_of(String, Zlib.zlib_version)
     end