Objectives: To evaluate the impact of pneumoperitoneum on pulmonary fimctions, hemodynamic variables and  frequency and intensity of shoulder tip pain  (STP)  in patients  undergoing laparoscopic cholecystectomy  (LC). Patients  & methods: Fifty chronic calcular  cholecystitis patients were allocated  to high­ pressure (HP) group (13-15 mmHg) and low-pressure (LP) group (9-11 mmHg). Mean arterial pressure (MAP), and heart rate (HR) measurements were obtained before (I'1), after induction of anesthesia  (I'2), 5 min. before  (T3), after insufflation (T4), 5 min. after tilting in reverse Trendelburgposition (T5)  and after exsu.fflation of C02 (T6). Duration of surgery, occurrence of intraoperative complications  and conversion to laparotomy, time till first ambulation, first oral intake and length of postoperative (PO) hospital stay were recorded. Severity of PO STP was assessed using visual analogue scale at 3, 6, 12, 24, and 48 hours. Forced vital capacity (FVC),forced expiratory volume in 1 sec (FEVJ) and FEVJ/FVC ratio were estimated 24 hours prior to and after surgery. Results: All patients passed smooth intraoperative course without complications or conversion to laparotomy. Mean operative data showed non-significant difference between both groups. At T4 and T5 HR and MAP measurements  were significantly higher in HP group despite the significant difference compared to other measures in both groups. Twenty-three  patients had STP with significantly  higher frequency and intensity in HP group.Mean duration till request of analgesia was significantly  longer in LP group. Pneumoperitoneum altered PO pulmonary function tests compared to preoperative values with significantly altered FEV1 evaluated as the percentage of change in HP group. Conclusion: Pneumoperitoneum irrespective of the pressure used affects pulmonary function tests andinduces hemodynamic changes with precipitation ofSTP,· however LP allowed significant amelioration of these effects despite that it could not abolish it, so it allows getting the advantages of laparoscopic surgery with minimal hazards.