Abstract The geometric parameters defining the flow passage of a new type drip emitter were selected to be design variables, and 16 cases were designed by using orthogonal experimental design method, and their hydraulic performance was tested at six operating pressures ranged in 50-250 kPa to identify the hydraulic characteristics and influences of these geometric parameters on them. The experimental results showed that the power, usually called flow regime index, in the flow rate-pressure relationships of 16 cases is in the range of 0.475-0.498, suggesting a rather good hydraulic performance. Based on range analysis on the results, it was found that the distance between the second baffle plate and the second orifice plate induces the greatest influence on the flow regime index, while the distance between the first baffle plate and the first orifice plate is responsible for the least influence. A regression model of the flow regime index with seven geometric parameters was established by employing multiple linear regression, and the followed analysis of variance showed that the correlation of the model is good. In terms of t-test, the distance between the first water baffle plate and the side wall, the central aperture of the first orifice plate and the distance between the second baffle plate and the second orifice plate have a significant effect on the flow regime index. Meanwhile, the verification test confirmed that the error between predictions and measurements is less than 5%. Thus, the flow regime index can be predicted accurately and reliably.