The research work on dewfall and its impact on growth and yield of Indian mustard crop grown with normal growing and terminal moisture stress conditions under open and dew sheltered situations was conducted. The total dew amount in the entire crop season ranged between 95.99 mm in open irrigated crop and 92.51 mm in open stressed crop. In dew sheltered conditions, the total dew amount recorded was 3.52 mm in sheltered irrigated and 2.86 mm in sheltered stressed crop. The meteorological parameters viz., evening relative humidity, minimum temperature and wind speed were significantly associated with dew occurrence. Minimum temperature, evening time relative humidity and wind speed parameters gave fair estimate of dewfall. There were significant variations in dew climatology in open and sheltered mustard crop. Input parameters viz., minimum temperature, relative humidity (evening) and wind speed gave a good estimate of dewfall, thus, may be used for prediction of dew occurrence and subsequent management of dew oriented plant protection measures in mustard crop in the region.