Abstract: Background and Objective: Germination is the first stage in a plant’s life, which can be affected by stress and conditions. Seed priming has been shown effective in producing earlier germination, better establishment in a range of crops in many diverse environments. This experiment was conducted to find out the effects of priming treatments on sesame seed germination under a range of drought conditions. Materials and Methods: Seeds were primed using sodium chloride (-2 bar) for halopriming, polyethylene glycol 6000 (PEG) (-2 bar) for osmopriming, distilled water for hydropriming for two exposing duration of 8 and 16 h and unprimed seeds for control. Germination percentage (Gmax), germination rate (R50), mean germination time (GMT), vigor index, Germination Index (GI), Germination Stress Index (GSI), energy of germination, root and shoot length and seedling weight were studied under 6 drought stress conditions (0.0, -3.0, -4.5, -6.0, -7.5 and -9.0 bar). Data were analyzed by means of SAS Software (9.1 versions) (SAS Institute 2001). Mean comparisons were carried out by Duncan’s New Multiple Range Test at the 0.05 probability level. Results: When osmotic potential declined to -9 bar PEG Gmax (47%), R50 (82%), GSI (41%), root length (92%), shoot length (98%) and seedling weight (76%) were reduced. PEG applied was the most efficient method in improving germination and emergence in all tests. Gmax, R50, root and shoot length and seedling weight were considerably improved, respectively (1, 2, 10, 10 and 8%) by this treatment. Conclusion: Results of this study showed that osmopriming with duration of 16 h enhanced the germination and seedling growth of sesame seeds under drought stress conditions. Based on these Results seed priming with PEG may be considered as a reliable procedure to increase the sesame drought tolerance.