Wound dehiscence is a postoperative complication encountered following abdominal surgery. A prospective randomized study was conducted to compare the incidence of wound dehiscence with a delayed absorbable and a nonabsorbable suture material in the mass closure of vertical laparotomy wounds. In one group, 100 patients were analyzed after closure with Prolene®, and in another group, 100 patients were analyzed after closure with Vicryl®. The incision was closed by continuous far and near suture technique using polypropylene (Prolene) suture in one group and a synthetic delayed absorbable polyglactin 910 (Vicryl) suture in the other group. There was significant difference in the incidence of wound dehiscence between the two groups: 6 % with Prolene and 17 % with Vicryl, (χ (2) = 5.944, 1 DF, P value = 0.0148). The overall incidence of wound dehiscence was 11.5 % in this study. The incidence of wound dehiscence in both the study groups was higher than expected as compared to previous literature. There was a significant difference between the two suture materials. In our study, Prolene is a better suture material for closure of vertical laparotomy wounds.