Transgender and gender diverse (TGD) women (i.e., individuals who were assigned male at birth and identify as women or trans women) experience trauma at disproportionate rates compared to cisgender populations. While trauma is associated with increased alcohol use among TGD women, research regarding factors that are protective of this association is scant. The stress-buffering hypothesis of social support suggests that perceived social support, defined as the judgment that social network members will be helpful when individuals experience stress, may buffer and reduce the association between trauma symptoms and alcohol use. However, this relationship has not been examined among TGD women. We examined whether perceived social support moderates the association between trauma and alcohol use among 89 TGD women. Exploratory multiple regression analyses provided support for this hypothesis, insofar as trauma symptoms were related to alcohol use by individuals with low, relative to high levels of perceived social support. Exploratory analyses demonstrated that this finding was driven by perceived social support from friends and family. Our results are the first to suggest that social support reduces alcohol use among TGD women and add to the literature on their trauma and alcohol use.