Discrimination against gay men, sometimes called gayphobia, is a form of homophobic prejudice, hatred, or bias specifically directed toward gay men, male homosexuality, or men who are perceived to be gay. This discrimination is closely related to femmephobia, which is the dislike of, or hostility toward, individuals who present as feminine, including gay and effeminate men. Discrimination against gay men can result from prejudicial reactions to one's feminine mannerisms, styles of clothing, and even vocal register. Within the LGBT-community, internalized issues around meeting social expectations of masculinity have been found among gay, bisexual, and transgender men.
In French academia, queer theorists have examined the unique ways in which patriarchy attempts to enforce both masculinity and heterosexuality on those with male bodies. The French queer and race theorist Louis-Georges Tin examined discrimination against gay men, and the historical development of the various forms of LGBT-related phobias under the umbrella of homophobia. He writes:
There has been an inverse movement of lexical differentiation operating at the heart of the concept of homophobia. Because of the specificity of attitudes towards lesbianism, the term lesbophobia has been introduced into theoretic discourses, a term which brings to light particular mechanisms that the generic concept of homophobia tends to overshadow. With one stroke, this distinction justifies the term gayphobia, since much homophobic discourse, in reality, pertains only to male homosexuality. Similarly, the concept of biphobia has also been proposed in order to highlight the singular situation of bisexuals, often stigmatized by both heterosexual and homosexual communities. Moreover, we need to take into consideration the very different issues linked to transsexual, transvestite, and transgender persons, which brings to mind the notion of transphobia.
In her 2017 text, The Women's Liberation Movement: Impacts and Outcomes, the German gender historian Kristina Schulz noted that within the Western media landscape during the 1970s' Gay Rights Movement, prejudice against gay men attracted more media attention than lesbophobia, largely due to the rhetoric of reactionary conservatives such as Anita Bryant, who suggested that gay men were sexual predators.
According to the French government, discrimination against gay men "is a form of homophobia that specifically affects men. Although it is primarily aimed at gay and bisexual men, it can also affect heterosexual men who are perceived as homosexual. Gay men may be targets of physical aggression or devalued by stereotypes linked to feminisation and hypersexualisation."
There is very clearly a difference in mechanisms between gayphobia and lesbophobia, and this translates into different types of aggression. Where the collective imagination over-sexualizes gay men and exerts strong verbal and physical violence against boys and men who are not considered sufficiently masculine or heterosexual; for women, on the other hand, the assertion of their lesbian identity will be further disqualified, minimized, reduced to a fad, or even sexualized as a prelude to heterosexuality.
In peer-reviewed studies which break down and distinguish homophobia separately between discrimination against gay men and lesbians, researchers have found statistically significant differences between heterosexual men and women in regards to their attitudes toward gay men. While no statistically significant differences were found in men and women in regard to lesbians, heterosexual men do demonstrate statistically significant elevated levels of animosity toward men they perceive as gay.
A 2021 study found that voters penalized openly gay candidates 6.7, 4.6, and 3.3 percentage points in the United States, United Kingdom, and New Zealand respectively. These differences were higher for right-wing voters and not statistically significant among left-wing voters.