A field study was carried out during 2023-2024 and 2024-2025 at Agriculture research station, Binjhagiri, Chatabar, Faculty of Agricultural Sciences, SOADU, Bhubaneswar with an objective to evaluate the effect of integrated use of closer spacing, herbicide and mulch on weed growth and yield of mustard. The soil of the experimental field was sandy loam in texture. The experiment comprised of twelve treatments, viz. pre-emergence application (PE) of pendimethalin at 0.75 kg/ha; mulching with rice straw 4 t/ha; mulching with biomass of Chromolaena odorata 20 t/ha; pendimethalin 0.75kg/ha PE followed by (fb) mulching with rice straw 4 t/ha; pendimethalin at 0.75kg/ha PE fb mulching with biomass of C. odorata 20 t/ha; closer spacing of mustard (30 cm x 10 cm) + pendimethalin 0.75 kg/ha PE; closer spacing + mulching with rice straw 4 t/ha; closer spacing + mulching with C. odorata 20 t/ha; closer spacing + pendimethalin 0.75 kg/ ha PE+ mulching with rice straw 4 t/ha; closer spacing + pendimethalin 0.75 kg/ ha PE + mulching with C. odorata 20 t/ha; hand weeding twice at 20 and 40 days after seeding (DAS) and weedy check. A randomized block design with three replications was used. The hand weeding twice at 20 and 40 DAS registered significantly lower total weed density and biomass with higher values of yield attributes and yield of mustard. It was closely followed by closer spacing + pendimethalin at 0.75 kg/ha PE + mulching with rice straw 4 t/ha which recorded maximum net return and returns/rupee invested and was found to be promising for realising effective weed management, higher productivity and profitability in mustard.