Among the numerous abiotic stresses restricting the crop production, salinity stress is the most significant one. Estimation of genetic variability and development of suitable selection criterion are fundamentals for development of salinity tolerant types of crop plants. Sixty accessions of Brassica napus were evaluated for salinity tolerance using hydroponics technique. Six sensitive and ten tolerant lines were selected and crosses were attempted in line × tester fashion. The resultant F1 crosses and their parents were evaluated at seedling stage using hydroponic culture technique and at maturity stage in a pot experiment. Data were recorded on various seedling (root length, shoot length, fresh root weight, fresh shoot weight, dry root weight, dry shoot weight, proline content, Na+/K+ ratio, osmotic potential) and morphological traits (days to 50% flowering, days to 50% maturity, plant height, number of primary branches, number of silique per plant, seeds per silique, oil content, thousand seed weight, yield per plant). Recorded data were analyzed to estimate the genetic variability, general and specific combining ability effects, heterosis, gene action and association among traits. Results showed that genetic variability existed in present breeding material that may be used in development of high yielding salinity tolerant Brassica napus. Combining ability analysis revealed that lines ZMR-2 and R-3 and testers Faisal and Shirlaee for seedling traits and lines R-3 and 23627 and tester Faisal for morphological traits were best general combiners for most of the traits under normal and salinity stress conditions. Crosses R-3×Laclone, RBJ-8007×Laclone and ZMR-1×ZMR-3 were best specific combiners for most of the traits under all treatments. Cross RBJ-8007×Laclone also had significant and positive mid parent, better parent and commercial heterosis for most of the traits under control and salinity stress treatments. Correlation and path analysis revealed that number of silique per plant, oil contents, days to 50% flowering and days to 50% maturity may be used as selection criteria for development of salinity tolerant types with higher yield as they showed significant association with yield per plant under salt stress conditions.