Uncontrolled intersection vehicle delay is of great significance for evaluating the intersection service level,so that it is necessary to study a relative practical delay calculation method.This paper analyzes vehicles operating characteristic;divides the vehicle delay into waiting delay and acceleration-deceleration delay;uses probability theory to derive an iterative method which includes the average service time and service time variance of every approach;describes the queue phenomenon of uncontrolled intersection with M/G/1 queuing system;proposes the average waiting delay formula;and puts forward the acceleration-deceleration delay of uncontrolled intersection by using the method of signal intersection for reference.It is showed that the theoretically calculated values are close to observed values of delay that come from an uncontrolled intersection of shi-zi street and xuan-wei street in Harbin.