A dental catalyst for chemical polymerization comprising an acidic compound, an organic peroxide such as cumene hydroperoxide, and aryl borate compound such as sodium tetraphenylborate, but without substantially containing amine compound. This catalyst is chemically highly stable, is easy to handle, is highly active, is less likely to be impaired by polymerization, and does not cause the cured product to be tinted or discolored, and is very useful for the dental restorative.
