Generally oscillation reaction occurs in a complex system containing oxidant, reductant, substrate, metal catalyst, and acid. However, we found at first time a unique oscillation system in dichloromethane which contains only vanadium complex. In order to make clear this interesting phenomenon, we investigated the system using a variety of methods and finally found the following interesting results : 1. The oscillation reaction occurs only in dichlromethane solution of[ V(IV) OCl_2(bpy)] or[ V(III) Cl_3(CH_3CN)(bpy)]. The oscillation reaction does not occur in any related halomethane solvent such as chloroform and dichloroethane. 2. The oscillation reaction was found to be aperiodic at a constant temperature. However, when the temperature pulse was applied to the solution, the oscillation become to follow the pulse, resulting in a periodic behavior. 3. Photo-degradation of dichloromethane triggers the oscillation reaction and peroxy-radical species generated in the decomposition reaction works as an oxidant. 4. The observed oscillation reaction can be simulated mathematically in terms of the Cobaltlater model.