Lentil is commonly grown as a rotation crop in east and southeast of Turkey. It is an important crop because of its high protein content of seed and straw for human and animal nutrition. Phosphorus in the soil has developmental activity in the plant's root growth. The effects of humic substances on plant growth, under conditions of adequate mineral nutrition, consistently show positive effects on plant biomass. An experiment was conducted to study the effect of different levels of humic acid and phosphorous on yield and yield attributes of lentil during 2008-09 and 2009-10 in Agricultural Faculty experiment field of Yuzuncu Yil University. The results of the study indicated that humic acid and phosphorus applications increased significantly the seed yield and yield components. Whereas the highest seed yield were obtained from 80 kg phosphorus ha(-1) with 1135 kg ha(-1) and 600 kg humic acid ha(-1) application with 1097 kg ha(-1) in the first year, the values were 80 kg phosphorus ha(-1) with 1756 kg ha(-l)and 600 kg humic acid ha ha(-1) application with 1625 kg ha(-1) in the second year.