This study was conducted in the tissue culture laboratory of the Horticulture Department, Faculty of Agriculture. Mansoura University during the period from 2002 to 2005, aiming to investigate the shoot multiplication and production of microtubers in in vifro of Sofanum tuberosum L. cv spunta and evaluated this microtubers under salinity conditions. Effect of different concentrations of NaCl (0.0. 0.5. 1.0. 2.0, 4.0, 6.0, and 8.0 giL) was recorded on shoot proliferation and mlcrotuben'zation. All parameters under this study (shoot length, number of both shoots and leaves ! explant and cluster fresh weight) were significantly decreased at the highest levels of salinity (6.0 and 8.0 gfL NaCl). However, number of shootsfexplant was significantly increased by 4.0 g/L NaCl. It is a matter of interest to mention that multiplication rate was not significantly affected by salinity up to 4.09fL NaCl. Survival percentage and number of shoots per explant at 4.0 glL NaCl were 81.10% and 6.85. respectively. However at 8.g!L NaCI these parameters were 47.50% and 2.14. respectively. Microtuber characteristics (number, weight, length and diameter) were recorded under saline condition. All these parameters were decreased by increasing NaCl concentration in the culture media and the decrease was significant at 6.0 and 8.0 glL NaCl. The number of microtubers per shoot was not significantly decreased by increasing salinity level up to 4.0 giL NaCl ( 2.55) , while at 6.0 and 8.0 glL NaCl was significantly decreased (2.14 and 1.53, respectively).