Chemical methods are the most convenient and economical for wax precipitation and deposition prevention. The chemical additives so far in use have varied limitations, ranging from high cost to limited spread of crude oil that a particular additive can handle. The influence of cheaper natural chemicals, obtained from plant seeds (jatropha-JSO, rubber-RSO and castor-CSO) on the rheological properties and wax deposition tendencies of Nigerian waxy crude oil were investigated. Previously tested synthetic chemical additives (triethanolamine-TEA and xylene) were simultaneously examined too on the crude oils for comparative study. Four different crude oil samples obtained from Niger Delta region of Nigeria used for the study were characterized to obtain their hydrocarbon composition, wax content, pour points, viscosities, specific gravity and APIg using standard methods. The rheological properties such as apparent viscosity, plastic viscosity, yield stress were determined for the crude oils doped and undoped with the chemical additives using Fann VG Standard Viscometer. The results obtained revealed that oils from the three seeds could be used as flow improvers and pour depressants for Nigerian waxy crude oil. Jatropha and castor seed oils depressed the pour point than the previously investigated triethanolamine. They are capable of depressing the pour point up to about 17 C, and they can also reduce the viscosity of the waxy crude oil appreciably within 0.1-0.3%(v/v) dosage concentration. Also, CSO could exhibit as high as 77.7% paraffin inhibition efficiency (PIE) and JSO 73.5% at low concentration of doping.