The search for a viable alternative to freshwater such as the use of wastewater to irrigate ornamental plants has become particularly important due to Egypt's water scarcity problems. Researchers in this field should increase their efforts to introduce innovative approaches that allow for the efficient use of wastewater while maintaining the integrity of the agricultural system.  Therefore, this research was conducted to evaluate the effect of irrigation with water of different salinity levels [EC=475, 1000 and 2000 ppm] on Croton plant. In addition, the effects of spraying cobalt (Co) and selenium (Se) at different rates (0.0, 2.5, 5.0 mgL^-1) were studied. The study evaluated various parameters of the Croton plant, including the plant height, leaf area, nitrogen, phosphorus, potassium, chlorophyll a & b,anthocyanin and antioxidants. It is noteworthy that when Croton plants were irrigated with fresh water (EC=475ppm), they showed the highest values for all the parameters studied except for antioxidants, which showed the opposite trend. Also, as the salinity of the irrigation water increased to 1000 ppm and then to 2000 ppm, the values of all the parameters gradually decreased except for antioxidants which gradually increased with increasing salinity. On the other hand, both cobalt and selenium applications resulted in improvement of the Croton plant performance, especially when the plants were irrigated with saline water (EC=1000 and 2000 ppm). In terms of effectiveness, the order from most effective to least effective treatments was as follows;Se (5.0 mgL^-1)> Co (5.0 mgL^-1)> Se (2.5 mgL^-1)> Co (2.5 mgL^-1)> control group.