An experiment was conducted during summer 2020 at Zonal Agricultural Research Station, UAS, GKVK, Bangalore to study the bio-efficacy of pyroxasulfone for controlling weeds in summer maize. Treatment consisted of pre-emergence application of pyroxasulfone 85% WG at 125, 150, 175 and 300 g/ha and was compared with atrazine 50% WP at 2000 g/ha along with unweeded control and weed-free treatment. Treatments were arranged under randomised complete block design with 3 replications. Weeds caused yield reduction to the tune of 32% in summer maize. Results revealed that application of pyroxasulfone reduced weed-crop interference effectively which was significantly superior over atrazine. The per cent increase in maize yield due to pyroxasulfone treatment in its corresponding doses of 125, 150, 175 and 300 g/ha was 21, 18, 14 and 7%, respectively over unweeded control treatment. Increasing the dose of pyroxasulfone beyond 125 kg/ha reduced the yield of maize.