An aggregate signature scheme allows n signatures on n distinct messages from n distinct users to aggregate a single signature. The main benefit of such schemes is that they allow bandwidth and computational savings. Since Boneh et al.’s aggregate signature scheme from pairings, there exist several trials for constructing ID-based aggregate signature schemes. However, their computational complexity for pairing computations grows linearly with the number of signers. In this paper, we propose an efficient ID-based aggregate signature scheme with constant pairing computations. We also give its security proof in the random oracle model under the Computational Diffie–Hellman assumption.