A field experiment was conducted during rabi season 1998–99 to study the effect of weather parameters (sunshine hours, vapour pressure deficit, maximum, minimum and mean temperatures, and relative humidity) on radiation use efficiency in wheat. Five cultivars V 1 (WH 542),V 2 (PBW 343), V 3 (UP 2338), V 4 (Raj 3765) and V 5 (Sonak) were sown on three dates i.e. 25 th November, 10 th December and 25 th December. Delay in sowing from 25 th November to 10 th December significantly reduced the radiation use efficiency. Efficiencies varied from 1.24 to 2.85 gm dry matter MJ −1 of intercepted photosynthetically active radiation for wheat crop. Among varieties and sowing dates. Sunshine hours, vapour pressure deficit, maximum, minimum and mean temperatures of whole season were negatively associated while positive correlation existed for relative humidity with radiation use efficiel1cy.