Background: Although breast abscess is a serious common complication of lactational mastitis with a high morbidity rate, there is a lack of high-quality trials to define the best treatment option. The traditional management of lactational breast abscesses involves incision and drainage of pus along with antibiotics, which is associated with prolonged healing time, regular painful dressings, difficulties in breastfeeding, and the possibility of milk fistula with unsatisfactory cosmetic outcomes. We reported a novel way of applying primary closure after incision and drainage. The new method is applicable on all sizes of lactational breast abscesses, has a shorter healing time, no need for frequent painful dressings, early return to breastfeeding, and a more acceptable scar. Aim of the study: The aim of this study was to compare the effectiveness of primary closure following incision and drainage in treating lactational breast abscesses with the traditional open method. Methods: This prospective, randomized controlled trial was conducted in Universal Medical College and Hospital Limited, Dhaka, Bangladesh, and MH Somorita Hospital and Medical College, Dhaka, Bangladesh during the period from January 2020 to March 2021. In total 50 lactating women with breast abscesses were selected as the study population who were divided into two groups. In group A, 25 patients were managed by primary closure following incision and drainage and in group B, other 25 patients were managed by incision and drainage. All data were processed, analyzed, and disseminated by MS Office and SPSS version 26.0. Results: In group A, the VAS scores were lower than those of group B. In every day’s comparative VAS scores, there were significant correlations between the groups where p values <0.0001. The mean (±SD) hospital staying periods were 1.2±0.3 and 3.1±0.5 days in group A and group B respectively. The mean (±SD) healing times were 18.7±3.4 and 26.4±5.8 days in group A and group B respectively. In both the durations, p values were less than 0.0001, So, those differences were considered extremely statistically significant. In this study, ‘recurrence’, ‘sinus formation’ and ‘ugly scar’ were found in 8%, another 8%, and 28% participants respectively in only group B patients as major complications. But in the group A, no such complication was observed. Conclusion: Primary closure of lactational breast abscess following incision and drainage is an effective modality in treating patients with lactational breast abscess and it should be the first line of treatment, especially for larger and multilocular breast abscesses with intact overlying skin.