Two new copper(I) complexes, [Cu(bdmpm)2](PF6) (1) [bis(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)methane (bdmpm)] and [Cu(µ‐bdmpp)(MeCN)]2(PF6)2 (2) [2,6‐bis(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)pyridine (bdmpp)], were prepared by reactions of [Cu(MeCN)4](PF6) with bdmpm or bdmpp in MeCN. X‐ray analysis revealed that 1 is a mononuclear complex with the central Cu being chelated by two bdmpm ligands. 2 has a double‐stranded helicate structure in which each of the two [Cu(µ‐bdmpp)(MeCN)]+ cations is linked by the other bdmpp ligand. Both 1 and 2 exhibited high catalytic activity in the polymerization of methyl methacrylate (MMA). Even though the ratio of MMA to catalyst was raised up to 1 000:1, the PDI for 1 (reaction time was fixed at 5 h) is below 1.6 and the conversion is up to 66.0% while that for 2 (reaction time was fixed at 6 h) is below 1.5 and the conversion is up to 75.2%. In addition, the effects of solvents, reaction temperatures as well as ratios of MMA to catalyst were also investigated.