diff --git a/bin/review-epub2html b/bin/review-epub2html
new file mode 100755
index 000000000..d5d30bfa2
--- /dev/null
+++ b/bin/review-epub2html
@@ -0,0 +1,19 @@
+#!/usr/bin/env ruby
+#
+# Copyright (c) 2018 Kenshi Muto
+#
+# This program is free software.
+# You can distribute or modify this program under the terms of
+# the GNU LGPL, Lesser General Public License version 2.1.
+# For details of the GNU LGPL, see the file "COPYING".
+
+require 'pathname'
+
+bindir = Pathname.new(__FILE__).realpath.dirname
+$LOAD_PATH.unshift((bindir + '../lib').realpath)
+
+require 'review/epub2html'
+
+if File.basename($PROGRAM_NAME) == File.basename(__FILE__)
+  ReVIEW::Epub2Html.execute(*ARGV)
+end
diff --git a/lib/review/epub2html.rb b/lib/review/epub2html.rb
new file mode 100644
index 000000000..27a1e20d0
--- /dev/null
+++ b/lib/review/epub2html.rb
@@ -0,0 +1,133 @@
+#
+# Copyright (c) 2018 Kenshi Muto
+#
+# This program is free software.
+# You can distribute or modify this program under the terms of
+# the GNU LGPL, Lesser General Public License version 2.1.
+# For details of the GNU LGPL, see the file "COPYING".
+
+require 'zip'
+require 'rexml/document'
+require 'cgi'
+
+module ReVIEW
+  class Epub2Html
+    def self.execute(*args)
+      new.execute(*args)
+    end
+
+    def execute(*args)
+      if args[0].nil? || !File.exist?(args[0])
+        STDERR.puts <<EOT
+Usage: #{File.basename($PROGRAM_NAME)} EPUBfile [file_for_head_and_foot] > HTMLfile
+       file_for_head_and_foot: HTML file to extract header and footer area.
+                               This file must be contained in the EPUB.
+                               If omitted, the first found file is used.
+EOT
+        exit 1
+      end
+
+      parse_epub(args[0])
+      puts join_html(args[1])
+    end
+
+    def initialize
+      @opfxml = nil
+      @htmls = {}
+      @head = nil
+      @tail = nil
+    end
+
+    def parse_epub(epubname)
+      Zip::File.open(epubname) do |zio|
+        zio.each do |entry|
+          if entry.name =~ /.+\.opf\Z/
+            opf = entry.get_input_stream.read
+            @opfxml = REXML::Document.new(opf)
+          elsif entry.name =~ /.+\.x?html\Z/
+            @htmls[entry.name.sub('OEBPS/', '')] = entry.get_input_stream.read.force_encoding('utf-8')
+          end
+        end
+      end
+      nil
+    end
+
+    def take_headtail(html)
+      @head = html.sub(/(<body.*?>).*/m, '\1')
+      @tail = html.sub(%r{.*(</body>)}m, '\1')
+    end
+
+    def sanitize(s)
+      s = s.sub(/\.x?html\Z/, '').
+          sub(%r{\A\./}, '')
+      's_' + CGI.escape(s).
+             gsub(/[.,+%]/, '_')
+    end
+
+    def modify_html(fname, html)
+      doc = REXML::Document.new(html)
+      doc.context[:attribute_quote] = :quote
+
+      ids = {}
+
+      doc.each_element('//*[@id]') do |e|
+        sid = "#{sanitize(fname)}_#{sanitize(e.attributes['id'])}"
+        while ids[sid]
+          sid += 'E'
+        end
+        ids[sid] = true
+        e.attributes['id'] = sid
+      end
+
+      doc.each_element('//a[@href]') do |e|
+        href = e.attributes['href']
+        if href.start_with?('http:', 'https:', 'ftp:', 'ftps:', 'mailto:')
+          next
+        end
+
+        file, anc = href.split('#', 2)
+        if anc
+          if file.empty?
+            anc = "#{sanitize(fname)}_#{sanitize(anc)}"
+          else
+            anc = "#{sanitize(file)}_#{sanitize(anc)}"
+          end
+        else
+          anc = sanitize(file)
+        end
+
+        e.attributes['href'] = "##{anc}"
+      end
+
+      doc.to_s.
+        sub(/.*(<body.*?>)/m, %Q(<section id="#{sanitize(fname)}">)).
+        sub(%r{(</body>).*}m, '</section>')
+    end
+
+    def join_html(reffile)
+      body = []
+      make_list.each do |fname|
+        if @head.nil? && (reffile.nil? || reffile == fname)
+          take_headtail(@htmls[fname])
+        end
+
+        body << modify_html(fname, @htmls[fname])
+      end
+      "#{@head}\n#{body.join("\n")}\n#{@tail}"
+    end
+
+    def make_list
+      items = {}
+      @opfxml.each_element("/package/manifest/item[@media-type='application/xhtml+xml']") do |e|
+        items[e.attributes['id']] = e.attributes['href']
+      end
+
+      files = []
+      @opfxml.each_element('/package/spine/itemref') do |e|
+        files.push(items[e.attributes['idref']])
+      end
+
+      files
+    end
+  end
+end