The present study examined potential bi-directional associations between religiosity and first sexual intercourse. The sample, drawn from the National Longitudinal Survey of Youth, included 303 teens (22% Hispanic, 35% Black, 43% White; 53% male) aged 15-16 in 1996 and 17-18 in 1998. All teens included in the sample were virgins at Time 1. In the longitudinal analyses, higher Time 1 religiosity (a composite of importance of religion and frequency of church attendance) was associated with a lower likelihood of first sexual intercourse between Time 1 and Time 2. However, transition to sexual activity between Time 1 and Time 2 was not significantly related to Time 2 religiosity. Thus, results do not support a bi-directional association; instead, it appears that teens with higher levels of religiosity tend to delay sexual involvement more than those with lower levels of religiosity.