Internationalization of higher education has become an inevitable trend under the impetus of world economic integration and informationization. This paper adopts the information diffusion technique in the fuzzy information optimization method to construct an assessment model for internationalization development of vocational education. Explicit sample data are turned into fuzzy sets, information diffusion points are built using a two-dimensional average information diffusion model, and the estimated loss and probability distribution of information diffusion are calculated to assess the internationalization development level of vocational education. The constructed indicators set people’s awareness of the internationalization development of vocational education and the dissemination effect, analyzed the internationalization development trend of vocational education in the past five years by combining the Google search data, and explored the impact of internationalization development of vocational education based on the indicators of output level and quality level. The results show that the communication effects of internationalization of vocational education are all rated between (3.3, 3.6), and the attention to the internationalization development of vocational education has increased from 10% to 70% in six years. This study provides suggestions and strategies for advancing the internationalization of higher vocational education in China, which is conducive to steadily increasing the internationalization of higher vocational education in China and improving the level of schooling.