Most of the productive crude oil and gas basins in the world which includes the Niger Delta is usually characterized by complex geological settings and diverse crude oil signatures. This study evaluates the use of molecular biomarkers particularly hopanes for the geochemical characterization and differentiation of crude oils from four major oil fields: Imo, Nembe, Soku, Bonga, Kwale and Owaza. Crude oil samples were collected directly from production lines and subjected to chromatographic separation and analysis using Gas Chromatography Mass Spectrometry (GC-MS). Diagnostic ratios such as Ts/(Ts+Tm), C29/C30 hopane, oleanane/C30 hopane, C31S/C31R and sterane/hopane (0.16 to 0.87) were computed to assess depositional environment, organic precursor input, thermal maturity, biodegradation status, and inferred age of source rocks. The results revealed that the Imo, Nembe, and Soku oil fields exhibit high oleanane indices (0.68 – 0.84), indicating deltaic depositional environments dominated by terrestrial organic matter and suggesting a Tertiary age for their source rocks. In contrast, the Bonga crude lacked oleanane but contained gammacerane (G/C30 = 0.12), pointing to a stratified marine origin with algal input. Thermal maturity indicators placed all samples within the low to moderate maturity window, with Ts/(Ts+Tm) ratios of 0.53 (Imo), 0.41 (Nembe), 0.42 (Soku), 0.52 (Bonga); 0.51(Kwale) and 0.51 (Owaza). These values are consistent with oils that have not yet reached peak thermal maturity, while biodegradation assessments using norhopane levels revealed different microbial alteration, with Imo and Soku oils being the least degraded. Multivariate statistical analysis was used to identify the genetic relationships among the crude oil samples. The study demonstrates the effectiveness of molecular biomarker analysis in differentiating crude oil sources within a petroleum province. These facts are of significant relevance to petroleum system modeling, reservoir correlation, and optimization of exploration strategy in hydrocarbon - rich basins like the Niger Delta