Southeast Asia’s tropical peat-swamp forests (TPSF) are globally important for carbon storage and biodiversity conservation, but are at risk from multiple threats and urgently require improved management. Ants are often used as ecological indicators in monitoring programmes to guide adaptive management, but data on TPSF ants are scarce. We conducted a twelve-month study on ants in the Sabangau TPSF in Indonesian Borneo using baited traps, to compare community composition across three disturbance categories (forest gaps, forest edge and relatively undisturbed interior forest) and between dry and wet season. The three disturbance categories supported distinct ant communities across seasons. Differences in canopy cover likely underlie these changes in ant community composition. Surveying was more effective in the dry season, because ant capture rates were higher and more indicator taxa were identified than in the wet season, but overall ant community composition did not differ significantly between seasons. These findings suggest a potentially useful role of ants as ecological indicators in TPSF. Further surveys should be conducted in Sabangau and other TPSFs to test the transferability of our findings.