Defines the basic concept of fuzzy set pair logic with contact number as the true value. Considering the true degree and false degree of set pair true value, respectively we gives calculation rules of fuzzy set pair logic, established the fuzzy set pair reasoning forms in single domain and dual domain, and the inference rules are given. For the reasoning relationship between optional plan and each attribute, we establishment the set of true value contact function, and analyzing its order relation and lattice structure, establishment the lattice order decision-making model based on set pair reasoning, the application example is given in the end.