Abstract: The study was conducted to determine the effect of Azotobacter chroococcum (Azotobacter) application on quality and quantity forage of the rapeseed cultivars (RGS 003, Hyolla 401 and Hyolla 330) and the possibility of cultivation the rapeseed forage in summer. The experimental design was spilt plot laid out in randomized complete block with three replications. Different levels of Azotobacter (zero and one kg ha-1) and cultivars were randomized to main plot and sub plot units, respectively. Results showed that Azotobacter significantly affected on all quantity traits except plant height. There were significant differences among cultivars for dry matter, biomass, sub branch number, plant height and forage glucosinolate concentration. Therefore Azotobacter can be considered as growth promoting for rapeseed in the future studies. Also, RGS003 cultivar was better than other cultivars when Azotobacter was applied.