Health-related quality of life (HQL) was assessed before and after either moderately or highly emetogenic chemotherapy. When the pretreatment HQL in patients who did not vomit after chemotherapy (n = 203) was compared to those who vomited (n = 230), it was found that patients who did not vomit had better physical, role, and social function scores as well as a better global quality of life score than did patients who had one or more episodes of vomiting. Furthermore, in patients who did not vomit, the pretreatment fatigue and anorexia scores were better than in patients who did vomit. Thus, pretreatment HQL scores appear to have value in predicting which patients will experience chemotherapy-induced emesis. In the week following chemotherapy, HQL change scores from prechemotherapy values for cognitive function, global quality of life, fatigue, anorexia, insomnia and dyspnea were significantly worse in the group experiencing emesis than in the group who remained completely free of emesis. There were no differences in physical, role, emotional and social function attributable to chemotherapy-induced vomiting.