The glycaemic index (GI) and the glycaemic load (GL) of market green plantain was studied in Zaria, Nigeria. Ten volunteer diabetics and seven volunteer healthy subjects participated in the study. Fifty grammes of boiled plantain with stew and meat was served as the test meal while glucose (50grammes) was served as the reference food. The glycaemic index was calculated as the area under the blood glucose curve. The glycaemic indices in diabetic and healthy subjects were 68 and 69 respectively which are in the medium range. The glycaemic loads of this meal were 34 and 34.5 respectively which are high.  Serving portions may have to be reduced to 30 grammes of carbohydrates to help lower the glycaemic load. The GI of plantain falls within the medium category in both diabetic and control subjects. Recommending plantain as one of the food to be consumed by the diabetics without caution on the quantity to be taken at a time may have an adverse effect on them.