Objective: To investigate the relationship among emotional support of original family and in-law family and marital satisfaction of preschooler’s mothers, and the mediating role of maternal experiential avoidance. Methods: Totally 335 mothers of preschoolers from 3 kindergartens in Shuozhou City, Shanxi Province were selected as research subjects. The emotional support subscale of Support and Interference from Family of Origin Scale, the Acceptance and Action Scale, Second Edition, and the marital satisfaction subscale of Olson Enrich Marital Inventory were used to measure emotional support of original family/in-law family, maternal experiential avoidance, and marital satisfaction. Results: Emotional support of original family and emotional support of in-law family subscale scores were all positively associated with marital satisfaction subscale scores (β=0.78, 0.92). Maternal experiential avoidance had a partial mediating effect between emotional support of original family and mother's marriage satisfaction, accounting for 42.78%; and maternal experiential avoidance had a partial mediating effect between emotional support of in-laws family and mother's marriage satisfaction, accounting for 28.04%. Conclusion: Low-quality emotional support of of original family and in-law family is a risk factor for higher levels of experiential avoidance among preschool mothers, which in turn leads to lower marital satisfaction among preschooler’s mothers.