A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master’s in Life Science of the Nelson Mandela African Institution of Science and TechnologyThis thesis reports the repellency activity and toxicity of Commiphora swynnertonii exudates. The exudates were extracted using hexane and chloroform solvents. The crude extracts were tested for repellency activity at concentration of 110, 100, 90, 80, 70, 60 and 50 mg/ml against Rhipicephalus appendiculatus larvae. The crude extracts were further evaluated for the acute and subacute toxicity using albino mice and rats, respectively. The results showed that repellency activity appeared to be concentration and time dependent. In acute toxicity, oral administration of C. swynnertonii hexane and chloroform extract at a doses of 500, 1000, and 2000 mg/kg body weight induced no clinical signs of toxicity in the mice during 14 days of experimental period. However, C. swynnertonii chloroform extract showed some toxic properties in some of blood parameters and in vital organs (liver and kidney) of treated mice. In subacute toxicity, C. swynnertonii hexane extract showed significant change in some of hematological and biochemical parameters. Even though rats treated with C. swynnertonii chloroform extract did not develop any observable sign of toxicity, some toxic properties was observed in some of blood parameters and in vital organs (liver and kidney). It is concluded that, C. swynnertonii hexane and chloroform extracts considered as good repellency agents against Rhipicephalus appendiculatus larvae. For the toxicity evaluation, C. swynnertonii hexane extracts was nontoxic while C. swynnertonii chloroform extract had toxic properties deduced from change in blood parameters and internal organs of treated animals.