It is very important to select a proper investment and operation mode for utility tunnel to realize successful operation of utility tunnel. Hence, by analyzing several common investment and operation modes of utility tunnel in China, an index system for selecting investment and operation mode of utility tunnel is established by taking project characteristics, work efficiency, social benefits, economic benefits and project risks as criterion layer which including 18 indices; and the technique for order preference by similarity to an ideal solution(TOPSIS) is selected to quantitatively calculate the index. The combination method of analytic hierarchy process(AHP) and TOPSIS is used to overcome shortcomings that TOPSIS cannot determine the weight of the index; the cloud model is introduced to improve the AHP and TOPSIS respectively; further more, the uncertainty of expert evaluation language in the process of mode selection is fully considered to build the selection model of investment and operation mode of utility tunnel based on AHPTOPSIS improved by cloud model. The Bid Ⅰ of PPP project of a utility tunnel in Xi′an is taken for example to verify the fit degree of the selected model.