In the study, levels of various microplastics were measured in water samples taken from the River Niger in Onitsha. FTIR techniques were used to analyze water samples from the [001], [002], [003], [004], and [005] sample sites. Polyethylene, polyester, polypropylene, styrene ethylene butylenes, and polystyrene were the five microplastic types examined at (<100 um). Their respective mean concentrations (particles L-1) in the water samples fell between the ranges of 6.66 – 12.33, 1.67 – 2.33, 1.33 – 4.33, and 1.66 – 6.33. In all of the water sampling areas, polystyrene and polyester concentrations were found to be highest and lowest, respectively, in accordance with the distribution of plastic types. Polycyclic aromatic hydrocarbons (PAHs) and marine debris were found in the river water, which was the cause of the high concentration of polystyrene that was discovered there.