New times of minima of the W UMa-type eclipsing binaries AH Tauri and AH Aurigae, obtained at the Athens University Observatory using a 40-cm Cassegrain-type telescope, have been used together with all reliable timings found in the literature in order to study the period variation and search for the presence of a third body in each system. Their O-C diagrams are presented and apparent period changes are discussed with respect to possible Light-Time Effect (LITE) in the systems. A least square method has been used to compute new light elements (updated ephemeris of binaries and their period change rate) as well as the mass functions, their minimum masses and periods of the possible third bodies in each case.