The present experiment was carried out to compare the effects of cobaltous chloride and sodium thiosulfate used in the treatment of sheep poisoned with amygdalin. In the study, changes occuring levels of cyanide in the rumen liquor and levels of cyanide, thiocyanate, hemoglobin and methemoglobin in the blood, were determined. In the study, sixteen ewes, aged approximately two years old, were used. The animal on which the experiment was made was fasted from 5 p.m. a day ago to the complement of experiment the next day, Thus, cyanide contaminations due to feed and water were prevented. Amygdalin was given through the rumen probe in the doses of 1,5 mg/kg. Samples of rumen and blood were collected at 1,2,4,8,24,72. hours after amygdalin was given. Samples of the rumen were analysed in terms of the levels cyanide. Samples of the blood were analysed in terms of the levels cyanide, thiocyanate, hemoglobin and methemoglobin. lt was observed that cobalt chloride given in the doses of 5,1 O and 15 mg/ kg at thirty minutes decreased the level of cyanide from 0,21 O ug/ml to 0.079, 0.039 and 0.068 ug/ml at first hour, respectively. On the other hand, it was defined that sodium thiosulfate given in doses of 50, 400 and 600 mg/kg at thirty minutes decreased the level kof cyanide from 0.21O ug/ml to 0.139, 0.165 and 0.179 ug/ml at first hour, respectively. lt was established that cobaltous chloride + sodium thiosulfate given in the dose of 10+600 mg/kg at thirty minutes decreased the level of cyanide from 0.21 O ug/ml to 0.103 ug/ml at first hour. Cobaltous chloride used in the treatment of the cyanide poisoning was found to be more effective than sodium thiosulfate.