As an emerging form of cultural communication, microshort dramas have emerged in the audiovisual industry. In order to explore the optimization method of international communication of short microdramas, this paper takes the selected short micro-dramas of an international video platform as samples, selects the influencing factors of the international communication effect of short microdramas, constructs the optimization model of international communication of short micro-dramas by using Bayesian network, and adopts the Great Likelihood Estimation Algorithm as its parameter learning method. The performance of the Bayesian network model is explored through model comparison, node sensitivity analysis and scenario simulation. The results show that the Bayesian network model has good prediction performance, and its AUC value is greater than 0.8 in both training and testing results. The entropy reduction percentages of publisher’s fan number, video duration and localized creation are all greater than 0.07%, which have the most obvious influence on the effect of international dissemination of microshort dramas. Scenario simulation verifies the influence of each variable on the optimization of the international dissemination effect of micro-short dramas, and the probability value of the obtained optimal solution with a strong dissemination effect is 83.5%. It is recommended to actively guide the creation of high-quality products, carry out in-depth localized creation, accelerate the integration of art and technology, and strengthen the comprehensive governance of the industry, so as to promote the global dissemination of China’s online micro short dramas.