Phytochemical screening of the crude methanolic leaf extract of Vernonia amygdalina was carried out. The extract and its fractions were tested for in vitro anticoccidial efficacy against the unsporulated oocysts of Eimeria tenella by the oocyst sporulation inhibition model in a 96-well microtitre plate. Phytochemical analysis of the extract revealed the presence of alkaloids, tannins, saponins, glycosides, and triterpenoids. Different concentrations of the extracts, including 250 mg/ml, 125 mg/ml, 62.5 mg/ml, 31.25 mg/ml, 15.625 mg/ml, and 7.8 mg/ml, were tested against freshly prepared unsporulated oocysts of E. tenella. Triplicate assays were conducted for each concentration of the extract to screen for anticoccidial activity. The methanol extract and fractions showed activity against the oocysts of E. tenella in a dose-dependent manner. The sporulation inhibition rate was determined as effective when the result showed more than 50% inhibition at each concentration level of treatment. Only the methanol extract and its butanol fraction at the lowest treatment concentration of 7.8 mg/ml showed an inhibition rate of 55% and 68%, respectively. All treatments: methanol extract (100%), hexane fraction (100%), butanol fraction (100%), and aqueous residue fraction (58%) were active at the highest concentration of 250 mg/ ml. It is concluded that the methanol leaf extract of Vernonia amygdalina and its butanol fraction had better oocyst sporulation inhibition activity against Eimeria tenella and may further be explored for their anticoccidial properties.