LGBTQ people experience violence directed toward their sexuality, gender identity, or gender expression. This violence may be enacted by the state, as in laws prescribing punishment for homosexual acts, or by individuals. It may be psychological or physical and motivated by biphobia, gayphobia, homophobia, lesbophobia, and transphobia. Influencing factors may be cultural, religious, or political mores and biases.

Currently, homosexual acts are legal in almost all Western countries, and in many of these countries violence against LGBTQ people is classified as a hate crime. Outside the West, many countries are deemed potentially dangerous to their LGBTQ population due to both discriminatory legislation and threats of violence. These include most African countries (except South Africa), most Asian countries (except some LGBTQ-friendly countries as Japan, Taiwan, Thailand, Vietnam and the Philippines), and some former communist countries such as Russia, Armenia, Belarus, Poland, Slovakia and Serbia. Such violence is often associated with religious condemnation of homosexuality or conservative social attitudes that portray homosexuality as an illness or a character flaw.

Historically, state-sanctioned persecution of homosexuals was mostly limited to male homosexuality, termed "sodomy". During the Middle Ages and the early modern period, the penalty for sodomy was usually death. During the modern period (from the 19th century to the mid-20th century) in the Western world, the penalty was usually a fine or imprisonment. There was a drop in locations where homosexual acts remained illegal from 2009 when there were 80 countries worldwide (notably throughout the Middle East, Central Asia and in most of Africa, but also in some of the Caribbean and Oceania) with five carrying the death penalty to 2016 when 72 countries criminalized consensual sexual acts between adults of the same sex.

Brazil, a country with LGBTQ rights protections and legal same-sex marriage, is reported by Grupo Gay da Bahia (GGB) to have the world's highest LGBTQ murder rate, with more than 380 murders in 2017 alone, an increase of 30% compared to 2016. Gay men experience potentially fatal violence in several places in the world, for example by ISIS, stoning by Nigeria, and others.

In some countries, 85% of LGBTQ students experience homophobic and transphobic violence in school, and 45% of transgender students drop out of school.

The Torah, which contains the basis for the law codes of Judaism, contains, among prohibitions against a variety of sexual relationships in Leviticus, with one verse of prohibition against male-male intercourse in Leviticus 18:22. To contextualize the emphasis biblical authors had for this prohibition compare it to Leviticus 18:19's prohibition against a man having intercourse with a menstruous woman or the eight verses of Numbers 35:1-8 spent on describing city planning. A violent criminal penal code regarding same-sex intercourse is prescribed in the Middle Assyrian Law Codes (1075 BCE), stating: "If a man lays down with his own brethren, when they have prosecuted and convicted him, they shall stay with him and turn him into a eunuch".^{[citation needed]}

Many harshly enacted laws and penal codes that strictly prohibited the practice of sodomy are enforced and reinforced throughout the entire European continent to prosecute and punish those who were found guilty for their criminal offense from the 4th to 12th centuries.

During the Republican Era of Ancient Rome, the poorly attested Lex Scantinia penalized any adult male for committing a sex crime (stuprum) against an underage male citizen (ingenuus). It is unclear whether the penalty was death or a fine. The law may also have been used to prosecute adult male citizens who willingly took a receiving passive role in same-sex penetrative intercourse, but prosecutions are rarely recorded and the provisions of the law are vague; as John Boswell has noted. "If there was a law against carnally lustful relations between individuals of the same-sex, no one in around Cicero's time knew anything about it".