Two field experiments were conductedunder surface irrigation system during two successive winter growing seasons 2017/2018 and 2018/2019in private farm atEl Qantra-West, Ismailia Governorate,Egyptto evaluate the effect of the combinations of three levels of phosphorus fertilizer (0, 15.5 and 31.0 kg P₂O₅/fad.) and three rates of bio-fertilizers (300, 600, 900g Phosphorein/fad.) on yield, yield attributes and yield quality of two lentil varieties, Giza-51 and Sinai-1. Giza-51 variety surpassed Sinai-1 variety in plant height, number of primary branches/plant and 100-seed weight. Sinai-1 surpassed Giza-51 in number of pods/plant by (10.39% and 15.08%) and number of seeds/plant by (15.4% and 14.36%) in the first and second seasons, respectively. Also, Sinai-1 over weighted Giza-51 in pod yield/plant by 18.39and 10.99%, seed yield/plant by 20% and 22.09%, seed yield/fad., by 17.1% and 25.69%, straw yield/fad., by 7.92% and 8.26% and protein yield/fad., by 18.70%and 23.28%in the first and second seasons, respectively.Soil mineral fertilization with calciumsuperphosphate at the highest level (31 kg P₂O₅/fad.) accompanied with bio-fertilizer (Phosphorein) at 900 g/fad.gave the highest values of yield, yield attributesand protein yield/fad.in the two seasons. A significant interaction between varieties, phosphorus and bio-fertilization was recorded for number of secondary branches/plant, number of seeds/plant, 100-seed weight and straw yield (kg/fad.) in the first season and weight of pods/plant in the second oneas well as for seed yield (kg/fad.) and protein yield (kg/fad.) in the two seasons.