The reverse atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) was successfully carried out in 1-butyl-3-methylimidazolium hexafluorophosphate with 2,2'-azobisisobutyronitrile/CuCl2/bipyridine as the initiating system, which had been reported as not able to promote a controlled process of MMA in bulk. The living nature of the polymerization was confirmed by kinetic studies, end-group analysis, chain extension, and block copolymerization results. The polydispersity of the polymer obtained was quite narrow, with a weight-average molecular weight/ number-average molecular weight ratio of less than 1.2. In comparison with other reverse ATRPs in bulk or conventional solvents, a much smaller amount of the catalyst was used. After a relatively easy removal of the polymer and residue monomer, the ionic liquid and catalytic system could be reused without further treatment.