A field experiment was conducted at El- Osait, Al-Jabal Al- Akdar, Libya, during two consecutive seasons 2022-2023 and 2023-2024 To evaluate the effect of foliar application of potassium nitrate at levels of 0, 10 and 20 L ha-1 on the growth, yield, and quality of a local faba bean cultivar. The experiment was arranged in a randomized complete block design (RCBD) with four replications. Measured traits included: plant height, number of pods per plant, pod length, number and we right of seeds per pod and per plant, biological yield, seed yield, 100-seed weight, harvest index and seed protein content. Results indicated that foliar application of potassium nitrate significantly enhanced most growth and yield parameters, with the highest values 95. 71 and 106.27 cm for plant height, 7.67 and 7.03 pods/ plant; 16.14, 15.39 cm of pod length; 6.31 and 7.03 seed/ pod; 7.03 pods/ plant; 16.14 , 15.39 cm of pod length; 6.31 and 7.03 seed/ pod; 8.69 and 8.50 g of pod seeds weight; 7.67 and 7.03 pods/ plants; 40.41 and 35.43 seeds/ plant; 34.86 and 30.70g of plant seeds weight; 4260 and 8510 kg/ ha of biological yield; 2600 and 3510 kg/ ha of seed yield; 61.03 and 60.41 % harvest index; 50.46 and 64.59 g of 100- seed weight and 22.83 and 23.0 % of seed protein content, generally obtained at 20 L ha-1 compared to the control. Regression, correlation and determination coefficient analysis for all the parameters showed a strong positive relationship across treatments with slope (b), correlation coefficient (r) and determination coefficient (R2) in both the two seasons. These results confirm that kNo3 foliar application particularly at 20 L ha-1 can be an effective practice to improve the productivity and quality of faba bean under the environmental conditions of El-osiata, Libya................ Keywords:...........faba bean, potassium nitrate, foliar application.