Adsorption of polycyclic aromatic hydrocarbons (PAHs) on mineral surfaces plays an important role in many engineering fields, such as oil recovery and oil sand production. In this work, the adsorption behaviors of a PAH compound, violanthrone-79 (VO-79), on quartz surface were investigated at different temperatures by molecular dynamics (MD) simulation and atomic force microscopy (AFM). Our simulations demonstrated that with increasing temperature, the rate of adsorption increased, whereas the total amount of stably adsorbed VO-79 molecules hardly changed. On the other hand, the adsorption mode had a strong dependence on the temperature. At 323 K, approximately half of the adsorbed VO-79 formed a monolayer with their polyaromatic cores directly contacting and parallel to the quartz surface. The other half were in an aggregated form and adsorbed indirectly, via interaction with directly adsorbed molecules. The polyaromatic cores of VO-79 in the aggregates tend to be oriented slant to the surface. A transition from indirect to direct adsorption was observed as temperature increased, and nearly 90% of VO-79 molecules were adsorbed in direct form at 523 K. AFM imaging confirmed the observations in the MD simulations, showing that smaller and more uniformly distributed VO-79 aggregates adsorbed on the surface with increasing temperature. This work provides valuable insights, at the molecular level, into the effect of temperature on the adsorption of PAHs on mineral surfaces.