Recently, kale has become popular due to its nutritive components beneficial for human health. This plant is an important source of glucosinolates, which stimulate activities related to cancer prevention. In the present study, the effect of different nutrition solutions and different levels of selenium foliar application on the morphological and biochemical traits of kale was investigated. The experiment was carried out using a factorial based on a completely randomized design with three replications. The treatments included three different nutrition solutions and four levels of selenium (zero, 5, 10 and 15 mg/L of selenate). The results showed that the highest amount of fresh and dry weight of the whole plant and leaf area was obtained in plants grown in nutrient solution number three (with higher calcium and nitrate than solutions number one and two) and sprayed with selenium at 10 mg/L. In terms of the amount of biochemical compounds, the highest amounts of chlorophyll, carotenoids, and soluble carbohydrates were obtained in plants grown in nutrient solution number three and a selenium level of 10 mg/L. The highest amount of phenolic compounds was obtained in plants fed with nutrient solution number two and 10 mg/L selenium foliar spray.