To obtain an adhesive composition having excellent moisture-resistant adhesiveness to synthetic rubbers and having a short set time by incorporating a 2-cyanoacrylate with a silane or siloxane compound having a 2-cyanoacryloyl group at each end.

This composition comprises a 2-cyanoacrylate represented by formula I and a silane or siloxane compound having a 2-cyanoacryloyl group at each end, desirably, a compound represented by formula II. In the formulae, R is a 1-18C alkyl, a haloalkyl, an alkenyl, a 5-20C cycloalkyl, a cycloalkenyl, a 6-20C phenyl, an arylalkyl, or a heterocyclic group; R1 and R2 are each a 1-4C alkyl, a (substituted) phenyl, and, desirably, both of them are CH3 groups; n is 1-6, desirably, 4; and m is 0-20, desirably, 1. The amount of the silane or siloxane compound having a 2-cyanoacryloyl group at each end is desirably 1-50 wt.% based on the total composition.