A split-plot experiment based on randomized complete block design (RCBD) with three replications was planned at Experimental Farm, Agriculture Faculty, Zagazig University, Egypt during the two consecutive seasons of 2017/2018 and 2018/2019. Aiming to study the effect of different potassium fertilization rate (0.0, 24 and 48 K2O kg/feddan) and different kaolin concentrations (0.0, 15, 30 and 45 g/l) as well as their combination treatments on growth, yield components, fixed oil production, total chlorophyll content in leaves and some chemical constituents in seeds of fenugreek plants. Results indicated that growth parameters (plant height, branch number/ plant and total dry weight/plant), yield components (number of pods/plant, seed yield/ plant and /feddan) and chemical constituents (total chlorophyll, total nitrogen, potassium, total carbohydrates, mucilage and trigonilline content) were influenced by experimental factors. Furthermore, the highest rate of potassium fertilization recorded significant increase in these parameters compared to control. In the same trend, the highest values in this concern of Trigonella feonum-graecum was observed with 30 or 45 g/l of kaolin compared to control. Moreover, applied 48 kg K2O /feddan was more efficient than 24 kg and control when combined with kaolin at 30 or 45 g /l, in most cases. Generally, this combination treatments seems promising in enhancing fenugreek growth and productivity under Sharkia Governorate conditions.