The labor market impacts of women's age at marriage have recently received significant attention from social scientists. The focus of this literature, however, has been the developed world and almost nothing is known about how a delay in marriage affects labor market prospects of women in developing countries. This paper addresses this gap in the existing literature by providing the first comprehensive assessment of the relationship between women's age at marriage and own as well as spousal labor market outcomes specifically in context of a developing country. Using nationally representative household data from India, we find evidence of positive effects of women's age at marriage on their own and their spouses' labor market outcomes. To examine whether these effects are causal or arise due to selection into marriage, we use an instrumental variables-based empirical strategy that utilizes variation in age at menarche to obtain exogenous variation in women's age at marriage. Our results indicate that the positive effects of age at marriage of women on own as well spousal labor market outcomes are not causal and arise purely due to selection. The results are robust to addressing biases due to nonrandom selection of individuals into labor force. Our findings shed new light on theories of labor market in developing countries specifically through the lens of marriage.