PURPOSE: We aimed to demonstrate the success and reliability of a novel puncture, aspiration, injection, and reaspiration (PAIR) technique in liver hydatid cysts. METHODS: Percutaneous treatment with ultrasonographic guidance was performed in 493 hepatic hydatid cysts in 374 patients. Patients were treated with a new PAIR technique by single puncture method using a 6F trocar catheter. The results of this novel technique were evaluated with regards to efficacy and safety of the procedure and complication rates. RESULTS: Out of 493 cysts, 317 were Gharbi type I (WHO CE 1) and 176 were Gharbi type II (WHO CE 3A). Of all cysts, 13 were referred to surgery because of cystobiliary fistulization. Recurrence was observed in 11 cysts one month later. Therefore, the success rate of the PAIR technique was 97.7% (469/480). Minor complications (fever, urticaria-like reactions, biliary fistula) were seen in 44 treated patients (12%, 44/374); the only major complication was reversible anaphylactic shock which was observed in two patients (0.5%, 2/374). CONCLUSION: This novel modified PAIR technique may be superior to catheterization by Seldinger technique due to its efficiency, easier application, lower severe complication rate, and lower cost. Further comparative studies are required to confirm our observations.