Activities at large haulage vehicle parks contribute to environmental pollution in Nigeria through ambient air pollutants. This research seeks to evaluate the harmful effects of the air pollutants released by a haulage vehicle park situated along a major highway that serves as a critical transportation artery connecting Lagos to other areas of Nigeria. Thus, the effect of haulage vehicle activities on ambient air pollutants at a large haulage vehicle park in Oke-Ese, Ilesha, Nigeria, was investigated. Following the collection of all samples, an analysis was carried out on them, involving polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs). The amount of PAHs at this location was measured using a standardized method from the Environmental Protection Agency, employing a sensitive testing technique that can detect tiny amounts (0.5-50 pg/µl) of these pollutants. Similarly, the VOCs analysis was quantified by selected ion monitoring. Quantification of the ions (m/z) was performed using a carrier gas at a flow rate of 1 mL/min. ∑PAHs concentration of old haulage trucks (13.06 µg/m³) was greater than that of new haulage trucks (10.49 µg/m³) and commercial buses (12.46 µg/m³), while the exhaust pipe in each case emitted most ∑PAHs and VOCs, with the ripple effect evident in ambient air and surrounding buildings. The concentration of 1,3butadiene was higher in the old haulage trucks than in others. The study underscores the imperative need for regulatory measures to tackle the substantial impact of haulage vehicles on air pollution in order to preserve the air quality and ensure the well-being of individuals who use the major highway adjacent to the vehicle park.