C語言版：
1、 HTK（Hidden Markov Model Toolkit）：
HTK是英國劍橋大學開發的一套基於C語言的隱馬爾科夫模型工具箱，主要應用於語音識別、語音合成的研究，也被用在其他領域，如字符識別和DNA排序等。HTK是重量級的HMM版本。
HTK主頁：http://htk.eng.cam.ac.uk/
2、 GHMM Library：
The General Hidden Markov Model library (GHMM) is a freely available LGPL-ed C library implementing efficient data structures and algorithms for basic and extended HMMs.
GHMM主頁：http://www.ghmm.org/
3、 UMDHMM（Hidden Markov Model Toolkit）：
Hidden Markov Model (HMM) Software: Implementation of Forward-Backward, Viterbi, and Baum-Welch algorithms.
這款屬於輕量級的C語言HMM版本。
UMDHMM主頁：http://www.kanungo.com/software/software.html
C++版：
1、http://www.cs.ualberta.ca/~lindek/hmm.htm
2、http://www.shokhirev.com/nikolai/abc/alg/hmm/hmm.html
以上兩個是C++版本的，但是實現的是離散型的HMM。
Java版：
Jahmm Java Library (general-purpose Java library)：
Jahmm (pronounced “jam”), is a Java implementation of Hidden Markov Model (HMM) related algorithms. It’s been designed to be easy to use (e.g. simple things are simple to program) and general purpose.
Jahmm主頁：http://code.google.com/p/jahmm/
Python版：
http://www.biocomp.unibo.it/piero/PHMM/
Malab版：
Hidden Markov Model (HMM) Toolbox for Matlab：
This toolbox supports inference and learning for HMMs with discrete outputs (dhmm’s), Gaussian outputs (ghmm’s), or mixtures of Gaussians output (mhmm’s).
Matlab-HMM主頁：http://www.cs.ubc.ca/~murphyk/Software/HMM/hmm.html
Common Lisp版：
CL-HMM Library (HMM Library for Common Lisp)：
Simple Hidden Markov Model library for ANSI Common Lisp. Main structures and basic algorithms implemented. Performance speed comparable to C code. It’s licensed under LGPL.
CL-HMM主頁：http://www.ashrentum.net/jmcejuela/programs/cl-hmm/
Haskell版：
The hmm package （A Haskell library for working with Hidden Markov Models）：
A simple library for working with Hidden Markov Models. Should be usable even by people who are not familiar with HMMs. Includes implementations of Viterbi’s algorithm and the forward algorithm.
Haskell-HMM主頁：http://hackage.haskell.org/cgi-bin/hackage-scripts/package/hmm
注：Haskell是一種純函數式編程語言，它的命名源自美國數學家Haskell Brooks Curry，他在數學邏輯方面上的工作使得函數式編程語言有了廣泛的基礎。
CDHMM C++版：
連續HMM的C++實現：http://download.csdn.net/detail/luxiaoxun/4417043
注：這是網上找的，裏面實現有個連續的HMM-GMM的實現，代碼寫的很好，有些地方需要根據自己的需求改動。
參考：http://www.52nlp.cn/several-different-programming-language-version-of-hmm