Niger seed (Guizotia abyssinica Cass.) is a multipurpose plant that has imported to Iran as a bird seed and doesn't have any scientific report in Iran. In order to evaluate the agronomic and physiological characters of Niger seed (as an oil seed and medicinal plant) in different seasons and sowing dates, some acts such as authentication of this species was done. Niger seed has been sown in autumn, spring and summer. Also in summer the effect of sowing date in a completely randomized design with 4 replications and 3 treatments (9 June, 21 June and 3 July) was evaluated in Isfahan province in 2010. According to the results, autumn and spring were not suitable season of cultivation of this plant and it can be grown in summer successfully. The effect of various summer sowing date, on most of the measured traits were significant. The best planting date was about the third planting date in Isfahan climatic conditions. The highest value of the number of capitula per plant (59.07), 1000 seed weight (3.39), seed yield per hectare (874.7 kg), number of seeds per plant (1510), seed oil (47.33) were obtained from the third sowing date. While the highest plant height (150.1cm), days to 50% flowering (67), days to 80% maturity (110) was recorded from the first sowing date.