A bus passenger flow prediction method based on small sample data comprises the following steps: firstly, counting bus passenger flow card swiping data and code scanning data of a certain line of Hangzhou to obtain a bus passenger flow change rule; then, utilizing bus passenger flow data characteristics to extract bus passenger flow data characteristics; and establishing a bus passenger flow support vector machine model according to the bus passenger flow data characteristics; and finally solving a mean square error between the passenger flow prediction value and the passenger flow actual value to verify the effectiveness of the passenger flow prediction model. According to the method, the bus passenger flow of the fourth day is predicted based on the support vector machine model by utilizing the three-day code scanning data and the card swiping data of a certain bus route, and an instance result shows that a prediction result has relatively high prediction precision.