A dental composition which comprises (A) a phosphoric acid group-containing monomer, (B) a carboxylic acid groups-containing monomer and (C) water as main components in amounts of 0.5 to 50% by weight, 1 to 50% by weight and 5 to 90% by weight, based on the composition, respectively; and a dental adhesive kit comprising a dental primer composition containing the monomer (A) and water and an adhesive containing a carboxylic acid-containing polyfunctional monomer and a polymerizable initiator.