The present study aimed to evaluate new promising mutant lines for canola under three generations (M₆, M₇ and M₈) and different locations [Ras-Suder-Sina (saline) and Inshas (harsh and poor fertility land)] for seed yield and its attributes, i.e. plant height, No. of pods/plant, seed weight/plant and 100 seed weight, as well as oil and protein content with comparison of the mother varieties. Studying the stability of new mutant lines during three generations (2014, 2015 and 2016) under two locations. The evaluation of mutant lines for seed yield and its attributes of mutant lines showed that lines 11,63.74 and 92 possessed highly significant than the other mutants and their parents for No. of pods/plant and seed weight/plant in both locations. The results confirmed more stability for mutant lines at Inshas location than at Ras-Suder location. The genetic response of genotypes under different locations confirmed the more stability of line 8 than the other mutant lines followed by lines 11, 66, 74 and 75. Oil percent was highly correlated with seed yield and its attributes as well as the improvement of seed yielding lead to improvement of oil percent. Protein content showed a negative correlation with almost yield criteria except for seed weight. The important remark of these results is the plant height as morphological criteria could be used as morphological marker for selection of high yielding new lines of canola. The results concluded that line 8 followed by lines 11, 66, 74 and 75 are excellent new genotypes which could be introduced in breeding programs to obtain new Egyptian canola varieties.