A female in her twenties was found dead in her room. She had received medications for depression and panic disorder, and had attemped suicide several times. Many packets of prescribed drugs, including paroxetine, were found near the corpse. At autopsy, the lungs were edematous. The organs were slightly congested with putrefactive change. Autolytic rupture, considered as gastromalasia, was observed in the anterior cardiac portion of stomach wall. Toxicological examination revealed 0.78, 3.20 and 17.63 microg/ml of paroxetine in the heart blood, femoral blood and urine, respectively. Acetaminophen and phenobarbital were also identified within therapeutic or sub-lethal levels. Taking into consideration postmortem diffusion of drugs, we evaluated postmortem data and concluded that the death was mainly due to toxicity of paroxetine with serotonin syndrome.