Provided is an adhesive composition which can form a cured product that is high in shear adhesion strength, peel adhesion strength and impact adhesion strength and particularly is excellent in cold/hot cycle resistance of adhesion strength. The adhesive composition comprises (a) a 2-cyanoacrylic acid ester, (b) a high molecular-weight component compatible with 2-cyanoacrylic acid ester, (c) a multifunctional 2-cyano-3-vinylacrylic acid ester, and (d) an onium salt represented by the following general formula (1): C+A−  (1) wherein, C+ represents an onium cation and A− represents an anion which does not substantially initiate polymerization of the 2-cyanoacrylic acid ester, and the components (a)-(d) are contained in predetermined amounts.