Cannabis is the most widely abused illegal substance in many countries of the world presently. It acts on the higher nerve centers and produces a feeling of intoxication with hallucination. Its main component, delta-tetrahydrocannabinol, produces the ‘high’ feeling that most users crave. Adolescence is the age of continued neuromaturation and most users experiment at the adolescent age. The aim of this research is to evaluate the histological effects of Cannabis sativa on the visual pathway of adolescent Wistar rats. A total of twenty-four (24) adolescent Wistar rats were recruited primarily for this study. They were randomly divided into four groups of six rats each labelled A, B, C, D which include the Control, Low Dose Group, Medium Dose Group and High Dose Group respectively. Administration lasted for 21 days with the Control group being administered pelletized rat chow and clean water ad libitum, the Low Dose group being administered 150 mg/kg body weight of the rat, the Medium Dose group being administered 250 mg/kg body weight of the rats and the High Dose group being administered 500 mg/kg body weight of the rats. At the end of the 21-day administration, the animals were sacrificed and the brain tissue specimens were excised and processed. The general histological demonstration of the superior colliculus, lateral geniculate body and the visual cortex was done using the H & E and Luxol Fast Blue Staining Techniques. There were observable effects of Cannabis on the body weight after administration. There were no serious morphologic changes in the organ weight in Groups B and C, but there were indications of such in Group D. The observable histologic effects of cannabis on the visual cortex are specific on neuronal morphology, spatial distribution of neurons and glia and neurophil integrity and this is dose-dependent.