Although some bisexual men experience conventional sexual attraction to both males and females, others have less obvious sexual interests underlying their bisexual identity, attraction, or behavior (i.e., bisexual phenomena). Accordingly, it has been proposed that some men's bisexual phenomena are motivated by autogynephilia, a male's propensity to be sexually aroused by the thought or image of being a woman. For these men, sexual attraction to males is secondary to their autogynephilia, rather than a reflection of conventional attraction to males. The present study examined how common autogynephilia is among bisexual cisgender men, and how autogynephilic bisexual men may differ from non-autogynephilic bisexual men in their sexual interests and behavior, uncertainty about their sexual orientation, and gender-related experiences. We recruited a large sample of bisexual-identified men (n = 254) via Prolific to complete an online survey. Of the sample, 35% (n = 89) endorsed at least half of the items on a measure of core autogynephilia. Consistent with past research on autogynephilia, autogynephilic bisexual men reported more paraphilic sexual interests than non-autogynephilic bisexual men. Of clinical importance, autogynephilic bisexual men reported less certainty about their sexual orientation, elevated childhood and adult gender nonconformity, and elevated gender dysphoria relative to non-autogynephilic bisexuals. These findings suggest that a substantial minority of bisexual men experience autogynephilia, and that future research should consider the unique experiences and needs of autogynephilic bisexual men, including how else they might differ from other bisexual men.