Background: division of the parenchymal lung for lobectomy is performed in patients who have an incomplete fissure. A stapler device can reduce postoperative air leak, but it is expensive. Objective: to investigate the advantage of using a stapler, in terms of postoperative air leak and cost, compared to handsewn techniques. Method: a non-blinded randomized controlled trial was conducted in Chiang Mai University Hospital, Thailand, from November 15, 2011 to September 30, 2012. Fifty-three adult patients were randomized to undergo a hand-sewn technique (27 patients) or stapler closure (26 patients). Results: postoperative air leak in the stapler group was less than that in the hand-sewn group (7.7% vs. 29.6%, p=0.044), and the duration of air leak in the stapler group was significantly shorter than that in the hand-sewn group (1.0 vs. 13.4 days, p=0.032). The cost of treatment was not significantly different between groups; however, the total cost in the stapler group was less than that in the hand-sewn group (mean difference 4454 Thai baht (US 144.75). Conclusion: a stapler reduces postoperative air leaks and the duration of air leaks. Furthermore, the total cost of treatment was comparable. Therefore, using staples may provide substantial financial benefits.