Although Nigeria has a high incidence of violent conflict and is divided along ethno-religious lines, no study has, to the best of my knowledge, examined the effect of violent conflict on hostility towards ethnic and religious outgroups using representative data for Nigeria, nor the differential effects of violent conflict on outgroup hostility among Nigerias Muslim and Christian populations. This study does so. The instrumental variable regression results showed that among Nigerias population, violent conflict has a positive effect on outgroup hostility. A plausible mechanism through which this occurs is that violent conflict erodes trust and makes ethnic and religious fault lines salient, which in turn leads to outgroup hostility. When I broke down the data based on religious affiliation and estimated some models using the Muslim and Christian subsamples of respondents, the analysis showed that violent conflict has a positive effect on outgroup hostility only among Christians.