The impact of anti-coccidial agents; allicin oil and diclazuril, on growth and mortality rates, lesion scores, oocyst output, histopathology, and caecal tissue anti-oxidant/oxidant status on caecal coccidiosis in broiler chicks was studied. 160 one-day old, unsexed Cobb breed broiler chicks; were divided into 8 equal groups (20 each). Group 1: negative control. Group 2: positive control (infected orally with field strain of Eimeria species sporulated oocysts (1×105/ml)/bird on the 14th day of age. Group 3: Infected and treated with 1 ml/L tween 80 in drinking water from the first day of appearance of bloody diarrhea for 5 successive days. Group 4: Infected and treated with allicin oil on feed from 1st day of age at a dose of 30ml/ton feed. Group 5: Infected and treated with diclazuril on feed from 1st day of age at a dose of 1ppm. Group 6: Infected and treated with allicin oil in drinking water at a dose of 1ml/10L from first day of appearance of bloody diarrhea for 5 successive days. Group 7: Infected and treated with diclazuril in drinking water at a dose of 0.5ml/L from first day of appearance of bloody diarrhea for 5 successive days. Group 8: Infected and treated with dicalzuril plus allicin oil in drinking water at the same doses for 5 successive days. On the 7th and 12th days PI, infected chicks fed allicin oil or diclazuril showed a significant (p<0.05) reduction in lesion scoring before returning to normal on the 17th day PI. Infected chicks treated with therapeutic doses of allicin oil or with diclazuril induced a significant decrease of lesion scores than the positive group only. Group 8 was able to induce more reduction of lesion scores compared with other experimental groups. On the 7th day PI, CAT enzyme activity and MDA concentration increased in all infected groups when compared to negative one whereas on 12th and 17th day PI, all treatment protocols induced a decrease when compared to infected non-treated groups. All treatment protocols showed an elevation in SOD enzyme activity when compared to non-treated.