The IUPR (OBD monitoring frequency) data of 200 in-use China V cars were randomly collected in Beijing. And the characteristic distributions of the IUPR monitoring values were tested by driving four kinds of typical cars on actual road, then the results were compared with experimental tests under New European Driving Cycle (NEDC). The results showed that the catalytic converter and oxygen sensor of OBD system could be monitored for collection vehicle, and the monitoring rates of EGR and secondary oxygen sensor could reach 74% and 91%respectively. At present, 3.9timesignition cycles could meet an IUPR monitoring conditions on average. The IUPR average values for each monitoring items were far greater than the China V limit value of 0.10. However, there were some differences for monitoring value distribution. Catalytic converter and oxygen sensor monitoring rates were both 92%. And the monitoring of the vehicle emissions could be realized basically under indoor NEDC, but the test results on 4 actual road indicated that different vehicles had different IUPR monitoring results for molecule adding 1. OBD system was difficult to achieve effective monitoring of vehicle exhaust emission for the traffic jams and low speed. Therefore, it is necessary to combine the actual conditions in Beijing to further improve the monitoring conditions of the vehicle OBD system, and the effective control of the vehicle emission control system will be achieved in Beijing.