This study estimated the association of cultural and social mechanisms with Korean American women’s drinking behaviors. Data were drawn from telephone interviews with 591 Korean women selected from a random sample of households in California with Korean surnames during 2007. About 62% of eligible respondents completed the interview. Respondents reported any lifetime drinking (yes/no), drinking volume (typical number of drinks consumed on drinking days), level of acculturation, and described their social network by assessing who encouraged or discouraged drinking (drinking support) or drank (drinking models). Multivariable regressions were used for analyses. About 70% (95% confidence interval [95%CI], 67 to 74) of Korean American women reported any lifetime drinking and current drinkers drank 1.18 (95%CI, 1.07 to 1.28) drinks on drinking days. Acculturation was not significantly associated with any lifetime drinking or drinking volume, while models and support for drinking were statistically significantly associated with a higher probability of any lifetime drinking and drinking more on drinking days. Each additional encourager, or one fewer discourager, for drinking in women’s social networks was associated with a 2% (95%CI, 1 to 3) higher probability of any lifetime drinking and drinking 0.25 (95%CI, −0.53 to 1.18) more drinks on drinking days. Each additional drinker in women’s networks was associated with a 4% (95%CI, 1 to 8) higher probability of any lifetime drinking and drinking 0.26 (95%CI, −0.05 to 0.60) more drinks on drinking days. Korean American women’s drinking appears to be strongly related to their social networks, though how women take on traits of their new environment was not.