Recently, saccharicterpenin extracted from Camellia oleifera seed meal has become a widely used feed supplement in animal husbandry. In order to assess its safety, this study was designed to investigate the toxicity and histopathological effects of saccharicterpenin on piglets. One hundred-fifty weaned pigs ((Yorkshire×Landrace)×Duroc), 75 males and 75 females with body weight (BW) of (7.35±0.29) kg, were randomly allotted to groups receiving diets supplemented with 0, 500, 1000, 2500 or 5000 mg kg–1 saccharicterpenin for 70 d. The diet with 500 mg kg–1 saccharicterpenin supplementation improved liver glutathione peroxidase (GSH-Px) activity, and the diet with 1000 mg kg–1 saccharicterpenin supplementation improved liver glutathione S-transferase (GSH-S) activity in piglets on d 70 (P<0.05). At 2500 mg kg–1, saccharicterpenin in the diets reduced average daily feed intake (ADFI) and average daily gain (ADG) of piglets from d 1 to 35, damaged the cardiac tissue and liver on d 35, and decreased white blood cell counts (WBC), activities of catalase (CAT) and GSH-Px, and concentrations of glucose (GLU) and urea nitrogen (BUN) in the blood of piglets on d 70 (P<0.05). In addition, diets with 5000 mg kg–1 saccharicterpenin supplementation reduced ADFI, ADG and increased diarrhea rates of piglets from d 36 to 70, and decreased hemoglobin (HGB) concentration and activity of CAT in the blood of piglets on d 70 (P<0.05). Moreover, at a rate of 5000 mg kg–1, saccharicterpenin supplementation increased pancreas index on d 35 and hepatic index on d 70, and damaged cardiac tissue, liver and spleen during the whole experimental period (P<0.05). These results suggested that dietary 500 mg kg–1 saccharicterpenin supplementation had beneficial effects on piglets, but excessive supplementation (2500 or 5000 mg kg–1) of saccharicterpenin in the diets could lead to growth retardation, hematological abnormalities and organ injuries.