Introduction: Herbal medicines are plant-based products used to treat various illnesses and their uses have dramatically increased over the past years in many developed and developing nations. Alchornea cordifolia is one of these plants with reports of its use in health promotion. Some plants exhibit toxicity due to the presence of phytochemicals inherent in them, therefore further studies are necessary in evaluating their toxicity levels. In this study, the sub-acute toxicity of ethanolic extract of Alchornea cordifolia leaves was investigated on the pituitary gland of adult male Wistar rats. The objective was to determine its effect on the histology of the anterior pituitary gland. Methods: Twenty (20) adult male Wistar rats weighing 140-200 were used for the research and were randomly divided into four groups labelled A, B, C. and D. Each group consisted of five (5) rats. Group A (normal control) received normal saline, while group B, C and D received 500 mg/kg, 1,000 mg/kg and 1,500 mg/kg body weight of Alchornea cordifolia extract respectively with the aid of an oral gavage. This was done for a duration of 28 days after which the rats were sacrificed and the pituitary gland obtained for histological analysis using H&E and PAS Orange G staining methods. Results: Histological observations showed that the various doses of the extract used had no detrimental effect of the anterior pituitary gland microstructure in groups B, C, and D when compared to group A. Conclusion: The findings showed that the various doses of Alchornea cordifolia leaf extract used in this study are non-toxic to the anterior pituitary gland in Wistar rats.