Background <p>While characteristics of an individual’s social network and reported loneliness may be linked, they can be distinct. Prior work indicates that gender moderates the relationship between social networks and loneliness; however, these relationships have not been investigated in American Indian adults. The current work investigates whether the relationship between characteristics of one’s social network (i.e., social network size and social integration) and loneliness is moderated by gender in a sample of Blackfeet American Indian adults.</p> Method <p>At Wave 1 of a longitudinal research project, we used linear regression to test whether gender moderates the relationship between social network characteristics and loneliness in a sample of 275 Blackfeet American Indian adults living in the Blackfeet nation in Montana. Our analyses controlled for age, education, and symptoms and depression and anxiety.</p> Results <p>Gender moderated the relationship between social network size and loneliness (<i>β</i> = − 0.15,<i> t</i>(265) = − 2.71, <i>p</i> = 0.01, <i>r</i>² change = .04), and the relationship between social integration and loneliness (<i>β</i> = − 0.14, <i>t</i>(265) = − 2.68, <i>p</i> = 0.01, <i>r</i>² change = .03). Women with small social networks reported significantly greater loneliness compared to men with similarly small social networks, and for women higher social integration (i.e., more social roles) related to lower loneliness, but this was not the case for men.</p> Conclusion <p>Social network characteristics predict loneliness for Blackfeet women but not Blackfeet men in this sample. Future work should elucidate predictors of loneliness for Blackfeet men and consider whether daily changes in social connectedness predict changes in loneliness and whether changes in social networks predict changes in loneliness.</p>