To settle the conflicts between stealth and resilience, the conception of software zero-watermarking is proposed by introducing image zero-watermarking into software watermarking in this paper, in which the key point is to choose a proper birthmark of the software, thus feature n-gram set is presented to be birthmark of the software. Then the software zero-watermarking scheme based on the feature n-gram set is introduced incorporating the idea of Shamir’s secret sharing. It is from experiments that the zero-watermarking scheme provides higher credibility and better resilience.