The present invention has its object to provide a reactive silyl group-containing room temperature curable composition which can give cured products having good recovery, durability and creep resistance and the mechanical physical properties of which can be adjusted so as to be adequate for the use as a sealing material or adhesive and, further, which is low in viscosity and good in workability. This object can be achieved by, for example, a curable composition which comprises an organic polymer (A) containing reactive silyl groups represented by the general formula (1) given below wherein a is 3 and an organic polymer (B) containing an average of 0.5 to 1.5 reactive silyl groups represented by the general formula (1) given below per molecule —Si(R13-a)Xa  (1).