Objective: Cisatracurium is approximately 3 times more potent than atracurium, devoid of histamine release and cardiovascular side effects and mainly eliminated by Hofmann degradation. Patients with liver disease exhibit abnormal response to most of muscle relaxants. This study was designed to evaluate the dose-response of cisatracurium in patients with mild-moderate liver impairment in comparison with healthy subjects. Methods: Eighty ASA physical status I-II patients of both sexes, scheduled for elective surgical procedures under general anesthesia, were divided according to their preoperative hepatic status and laboratory investigations into two groups; Group I (control group with normal liver functions, n = 40) and Group II (Liver dysfunction group, Child-Pugh Score A or B, n = 40). The doseresponse curve was constructed, ED 50 and ED 95 were estimated. Results: The preoperative laboratory parameters showed statistically significant differences between the two groups regarding serum albumin, total bilirubin, ALT, AST, PT, PC and INR. The operative data showed statistically insignificant difference between the two groups regarding the 1st dose response (p = 0.152), the estimated ED 80 (p = 0.886) and the calculated 2nd dose (p = 0.886) and statistically significant differences between the two groups regarding the 2nd dose response (p = 0.006), the measured ED 50 (p = 0.010) and the measured ED 95 (p = 0.001). In conclusion, the measured ED 50 and ED 95 through two-dose dose-response curve technique were clinically insignificant from using the single-dose technique. The dose-response curve of cisatracurium in patients with chronic liver disease was clinically insignificant in comparison with healthy subjects.