Abstract: How to effectively protect leading technologies is a common problem faced by modern innovative enterprises. Based on the 2017 Chinese enterprise patent survey data, this study examines the impact of R&D investment and innovation outsourcing on enterprise technology protection strategies. This paper divides the technology protection strategy into three categories: technology leadership, complementary asset portfolio and intellectual property protection. This paper also divides R&D investment into R&D intensity and R&D cycle. According to R&D organization form, this paper distinguishes innovation integration and innovation outsourcing. This study reaches the following findings: (1) Enterprises with high R&D intensity tend to protect technology through technology leadership and intellectual property rights. Enterprises with long R&D cycles tend to protect technology through intellectual property rights, especially through patent applications; (2) Enterprises that realize innovation integration are more inclined to adopt combined strategies of technology leadership, complementary asset portfolio and intellectual property rights. Enterprises that implement innovation outsourcing are more inclined to adopt complementary asset portfolios strategy;. Further subdividing the degree of innovation outsourcing, this paper finds that as the degree of outsourcing increases, enterprises will reduce their use of technology leadership and intellectual property protection strategies, and increase their use of complementary asset portfolio strategies.