Plantain (Musa spp.) is an important dietary source of carbohydrate in the humid tropical zones ofAfrica,Asia and South.Although there are reports on the physical, chemical and microbiological properties of plantain flour, little or no information is available on the effects of maturity time and pretreatment on the physicochemical properties of the flours. Thus, to promote and enhance the use of plantain flour, it is necessary to determine the physicochemical properties of the flour. Green Horn cultivar of fresh plantains was harvested at different periods of maturity fromweek 9 to 13 at Federal University of TechnologyOwerri university farm. The different batches were washed, peeled and cut into slices of 1cm thickness. Each batch of the sliced plantain was blanched, treated with citric acid, sodium metabisulphite, and milled into flour. The untreated plantain flour sample was used as control. Results showed no significant differences in the oil absorption capacity gelling point and bulk density of the flour samples, irrespective of the maturity time and pretreatment. However, there were significant differences in the water absorption (p<0.05) with the blanched sodiummetabisulphite-treated sample, having the highest value of 2.74 g/ g.Also, in the swelling index (p<0.05), the 13th week blanched sample had the highest value of 3.76 mL/mL. Irrespective of time of maturity, higher pH values were recorded for flours treated with sodium metabisulphite and blanched with values ranging from 6.87 - 7.54. Maturity time and different preheat treatments could be exploited for the development of multipurpose plantain flour.