Lettuce seeds of white paris cultivar were primed in -1 MPa of 7 different agents for 6 days at 20 °C then stored at 7 °C for 8 months and germinated at 20 °C. Lettuce seeds showed high response to seed priming after storage period; all priming treatments had significant differences compared with control (non primed seeds). Poly ethylene glycol (PEG) recorded the highest values of increasing germination percentage, coefficient of velocity, germination performance index, seedling fresh and dry weight and seedling length and reducing mean time to germination, time to 50% germination and (25%-75%) germination, and abnormal seedling.