Based on the common problems of the original fuzzy testing technique and the needs of RESTful API fuzzy testing, this paper proposes a white-box fuzzy testing method of REST API based on graph resource nodes for RESTful API software interface testing by using EvoMaster as a basic tool. The effectiveness of the fuzzy testing technique in this paper is analyzed. 21 apps with millions of downloads obtain more than 65,000 web request data and more than 8.5GB HAR files, and an average of 2,966 web request data is collected for each app. The REST interface filtering method of this paper’s fuzzy testing approach effectively and accurately targets interface objects for fuzzy testing. The number of generated requests of the REST API white-box fuzzing test method based on graph resource nodes in this paper is much lower than that of other tools, and the efficiency of vulnerability discovery is much higher than that of other tools. The test method in this paper improves the number of lines of code covered in six hours by an average of 53.86% over other tools. The test method in this paper can identify more vulnerabilities and can cover all the vulnerabilities found.