Objective The research aims to study the effect of palonosetron combined with low‑dose droperidol on QT interval. Methods One hundred with gynecological diseases undergoing laparoscopic surgery were divided into droperidol group (group F) and palonosetron plus droperidol group (group P+F) according to the random number table method (n=50). In group F, 1 mg droperidol was intravenously injected in patients 5 min after tracheal intubation, while in group P+F, 0.075 mg palonosetron and 1 mg droperidol were injected in patients 5 min after tracheal intubation. The mean arterial pressure, heart rate, bispectral index (BIS) and 12 lead electrocardiogram were recorded before administration (T0), 5 min (T1), 10 min (T2) and 20 min (T3) after administration. QT interval was measured and correct QT (QTc) interval was calculated according to the correction formula. The severity of nausea and vomiting 24 h after operation and the incidence of other adverse reactions were recorded. Results There was no significant difference in age, body mass index (BMI), American Society of Anesthesiologists (ASA) classification, and operation time between the two groups (P>0.05). There was no significant difference in heart rate, mean arterial pressure (MAP), BIS and QTc interval between the two groups during the whole observation period (P>0.05). There was no significant difference in QTc interval changes between the two groups (P>0.05); at T1, QTc interval values of group F and group P+F were slightly prolonged, but the difference was statistically significant compared with T0 (P<0.05). The severity of nausea and vomiting 24 h after operation in group P+F was lower than that in group F (P<0.05); there was no significant difference in incidences of other adverse reactions between the two groups (P>0.05). Conclusions Compared with droperidol alone, palonosetron combined with low‑dose droperidol did not further prolong the QT interval, and the antiemetic effect of the two drugs was better than that of droperidol alone.