Poor crop establishment can be major constrain to produce crop yield in marginal soils. The present study, was designed to investigate the effect of osmopriming on emergence and yield of maize (Zea mays L.). For osmopriming seeds were treated in aerated solutions of KNO3, KH2PO4 and polyethylene glycol 8000 (PEG8000) for 24 under room condition. Osmotic potential of the solutions were 0 (control), -0.5, -1.0 and -1.5 MPa. Control seeds were not treated. After osmopriming operation seeds were given 3 surfaces washing with distilled water then re-dried to near original weight under shad. Results showed grain and biological yields and some yield components affected by osmopriming treatments. Our results indicated solution kind and osmotic potential effected above characters. We obtain osmopriming of maize (Zea mays L.) seeds with polyethylene glycol 8000 (PEG 8000) at -0.5 MPa osmotic potential improved emergency, grain and biological yields compared with other treatments.