Data from 31 non-snowfed catchments in India having catchment areas less than 1515 km2have been analysed to develop a simple method for the estimation of monthly runoff for the monsoon months of June to October. One of the parameters of this method was found to vary with the catchment area, the percentage of forest cover in the catchment and the monthly average temperature. The value of another parameter of the proposed method was found to be constant during any one month in a hydrologically homogeneous region. The method proposed herein is useful for estimating the monthly runoff during the monsoon period from catchments having scarce data.