Abstract: Morphological, biochemical and technological characteristics were employed to identify lactic acid bacteria (LAB), isolated from traditional dairy products (Butter, Klila and Jben) was collected from different rural areas of the province of Djelfa. 277 lactic acid bacterial strains were isolated, with 170 (61.37%) of them belonging to lactic acid cocci others (38.63%) to the lactic acid bacilli. Their proportion were Lb. plantarium (13.72%), Lb. fermentum (09.75%), Lb. acidophilus (11.91%), Lb. helveticus (07.94%), Lb. paracasei subsp tolerans(06.14), Lb. casei subsp casei (08.66), Lc. lactis subsp cremoris (07.22%), Lc. lactis biovar (11.19%), Lc. dicetyllactis (10.11%), Lc. raffinolactis (08.30%), Leuconostoc lactis (03.61%), Leuconostoc mesenteroides subsp cremoris (01.44%). But these proportions of (LAB) were depending on the product tested as follows: Butter (14.08%), Klila (07.58%) and Jben (78.34%). Presumptive lactobacilli counts ranged from 1.5x10 to +3 3.4x10 cfu/ml, presumptive lactococci levels varied from 2.2.10 to 4.2.10 cfu/ml, presumptive leuconostoc +8 +2 +6 levels ranged from 2.8x10 to 7.2.10 CFU/ml. according to the method of Bradford (1976). Proteolytic strains +1 +3 GM99, GM27, GM31, GM10 and GM14 isolated from these traditional products have an average consumption rate of the casein equal to (833 µg/h, 820 µg/h, 809 µg/h, 530 µg/h and 216 µg/h), respectively. The proteolytic system involved in casein utilization provides cells with essential amino acids during growth in milk and is also of industrial importance due to its contribution to the development of the organoleptic properties of fermented milk products.