Objective: Establishing positive network resources and rebuilding drug free networks are key components of recovery process for women with substance use disorder (SUDs). Theory of planned behavior (TPB) posits that behaviors are determined by behavioral intentions, which are determined by three factors: attitude toward the behavior, perceived behavioral control, and subjective norms. The current study applied TPB to examine whether women’s personal social network characteristics (as subjective norms) were related to intentions towards, and/or a substance use relapse using prospective research design. Methods: Longitudinal data from 300 American women with SUD who received treatment at three county-funded, women-only intensive treatment programs was utilized for the current study. Results: Bayesian estimation path analyses indicated that attitude and abstinence self-efficacy at intake were not related to intention at the 6-month follow-up, but abstinence self-efficacy was directly related to substance use relapse by 12 months. Personal social network characteristics, number of treatment related persons in personal social network and sobriety support were significantly associated with intention at 6 months. The interaction between the numbers of treatment related persons and density was found on intention, suggesting that density strengthens the relationship between treatment related persons in network and intention. Intention to use substance was associated with relapse to substance use behavior. Conclusion Our findings support that personal social network characteristics can be considered as subjective norms in the TPB model. Personal social network interventions focusing on rebuilding consistent social norms against drug-using behaviors may decrease intention to use substance, which will lead to abstinence.