Abstract: A preliminary study of the rare earth element contents of some Niger Delta oils was carried out to evaluate their influence on petroleum system of the Niger Delta Basin. The oil samples were obtained from an onshore field in the Niger Delta and analyzed using Inductively Coupled Plasma Mass Spectrometric (ICP-MS) analytical technique. Four Light Rare Earth Elements (LREE), La, Ce, Nd and Pr were detected. Their concentrations varied from 0.009 to 0.49 ppb, 0.058 to 1.58 ppb, 0.01 to 0.47 ppb and 0 to 0.18 pbb, respectively. All the LREE showed significant and positive correlation with each other and also have significant correlation with aromaticity index (Toluene/nC7). The study showed that REE are not good for classification of oils but provide another tool in oil-oil correlation.