Sunlight assisted photocatalytic degradation of sulphur mustard was studied on sulphur doped titania nanocatalyst. The data obtained on doped titania nanocatalyst was compared with that of undoped and commercial TiO2 nanocatalysts. Sulphur doped titania nanocatalyst exhibited better activity than undoped, and commercial titania nanocatalysts towards the photocatalytic degradation of sulphur mustard. Sulphur doped TiO2 nanocatalyst degraded 100% of sulphur mustard within 120 mm. Whereas, it took 240 min for undoped TiO2 nanocatalyst, and 420 min for commercial TiO2 nanocatalyst to completely degrade sulphur mustard. Sulphur mustard degraded to acetaldehyde, carbon dioxide, disulfide, sulfoxide and sulfone of sulphur mustard, chloro ethyl vinyl sulfide, chloro ethyl vinyl sulfoxide, etc, due to photocatalysis facilitated by doped and undoped TiO2 nanocatalysts. Reduced band gap energy and increased visible light absorbance contributed to superior photocatalytic activity of S doped TiO2 nanocatalyst relative to other ones in the presence of sunlight. (C) 2014 Elsevier B.V. All rights reserved.