Field experiments were carried out for two consecutive kharif seasons of 1998 and 1999 at Agricultural Research Station Ragolu to study the effect of time of sowing and nitrogen levels on the weed dynamics in rice varieties under rainfed upland conditions. Weed population and weed dry weight differed significantly due to rice varieties, time of sowing as well as with levels of nitrogen. The weed density and weed dry weight were the lowest in the variety Pushkala (V1) when sown during second fortnight of June (D1) with non- supply of nitrogen (N1)