Joint monitoring model, a typical statistical big data to smart power investment, is the fundamental construction of joint monitoring in this paper with the limitation that needs to be solved urgently: inaccurate joint monitoring. The investment statistics problem of intelligent power investment statistics big data, the common genetic algorithm fails to solve it, and the result is not ideal. Accordingly, this article proposes the multi-party monitoring model of power investment statistical big data constructed by the decision model analysis, and studies construction of multi-party monitoring model of power investment statistical big data. (1) Use linear programming theory to identify the influencing elements, and split the indicators as requires of joint monitoring model building so that the interference factors in joint monitoring model construction can be decreased. Then, the linear programming theory is utilized to construct a decision model for analyzing the scheme of joint monitoring model building and its results are comprehensively analyzed. The MATLAB simulation results indicate that under certain decision evaluation criteria, the decision model analysis is more effective than traditional genetic algorithms in accuracy and time of affecting factors of joint monitoring model construction.