There is consensus that intimate partner homicide (IPH) is a gender crime and that it is one of the most extreme forms of violence. This study aims to identify the differences and similarities between men and women who committed IPH. Data were collected from 75 criminal cases: 12 homicides perpetrated by women against men and 63 by men against women. At the individual level, homicidal women and men showed previous criminal records, substance abuse and psychiatric disorders. The intimate relationships were similar: regarding its duration, they were underway at the time of the IPH, they had a history of previous separations and reconciliations, and also, they had history of abusive dynamics. Regarding the modus operandi of IPH, the victims were mainly killed in the house of the victim and/or the aggressor, usually with a white armour weapon or a firearm and under the influence of substances. Nevertheless, there were specific differentiating factors. Men who committed murder were described as the primary aggressors (79%), while the women who committed murder (46%) were previously documented as victims of intimate partner violence. Attempted suicide/suicide after the homicide was proven in 38% of the IPH offender men, with no women having committed or attempted suicide. The time elapsed between the homicide and the judicial sentence was six times higher for women, and the length of imprisonment was on average three times higher for men. Most of the men were convicted of first-degree murder, while the women were mostly convicted of second-degree murder. Practical implications of the results are discussed.