Proline is with stress tolerance in various plants species. In the present study, free proline was estimated in the root, stem and leaves of seven species of family Euphorbiaceae collected in Rainy and Summer seasons during 2015-2016 from Sikar district of Rajasthan. Result of study revealed that proline content was higher in summer seasons as compared to other season. The maximum content of proline was reported in the stem of Euphorbia hirta while minimum was in the root of Phyllanthus maderaspatensis.