References to different methods of cobalt detection in biologic material are given. Polarographic detection of cobalt in human urine and animal biologic material worked out by authors was used for evaluation of biologic MAC. Biologic material was limed by nitric and sulfuric acids. Sulfuric acid was carefully distilled off the burnt material. Mineralized material was dissolved in 10 ml of 1N hydrochloric acid, filtered and again steamed into moist salts. 2.5 ml of water, 0.5 ml of dimethylglyoxime (0.02 M), 2 ml of Na4P2O7 (0.2 M) and 5 ml of buffer solution (0.1 M NH4Cl and NH4OH) were added to limed mineral, than pH was driven to 9 by 1 = 2 drops of ammonia solution and after blowing through, the specimen was exposed to polarography in alternating current. ++Redox potential of cobalt is 1.18 V. The method can be used for detection of cobalt in urine of workers contacting with the stated metal. Sensitivity of the method is 0.02 Mkg/ml.