Based on the theory of S-R and S-O-R, the theoretical mechanism of the impact of the reference group and the perceived value on farmers’ environmental protection investment behavior has been analyzed and an empirical test has been conducted by using the survey data of 573 farmers in Jilin Province and structural equation model. The results show that the reference group and the perceived value have a significant impact in promoting farmers’ environmental protection investment, and the perceived value has a mediating effect in the influence of the reference group on farmers’ environmental protection investment. In terms of influential effect, the biggest overall impact comes from the informativeness of the reference group while the largest direct effect is from the perceived value. Multi-group structural equation estimation results show that the environmental investment behavior of highly-educated farmers is more likely to be influenced by the informativeness and the perceived value of the reference group while the environmental investment behavior of under-educated farmers is more likely to be influenced by the normativeness of the reference group. The environmental protection investment of farmers whose breeding income accounts for more than 50% of the total household income is more susceptible to the informativeness, normativeness and perceived value of the reference group.