Scanning tunneling microscopy is used to investigate the adsorption of toluene on the Si(001)-2X1 surface. At room temperature, adsorption occurs exclusively on top of dimer rows and results in several binding geometries. A metastable and weakly bound state is observed initially upon adsorption. This state converts to a more stable geometry. Conversions between the dominant adsorbed states are observed and can be induced by the scanning tunneling microscopy (STM) tip. These states closely resemble those of benzene on Si(001). Evidence that toluene interacts with more surface dimers than benzene is found in the bias dependence of the adsorbed states in STM images. Toluene decomposes upon annealing, leaving carbon on the surface.