Abstract： Objective To explore the crew and passengers' comfort on the Shijiazhuang-Taiyuan passenger dedicated line and physical factors,such as air pressure,noise,wind speed.Methods Comfort investigation of all the crew (n=244) and passengers (n=377) on the Shijiazhuang-Taiyuan passenger dedicated line at speed of 250 km/h and 200 km/h and the detection of the air pressure,noise and wind speed were performed in 2011.Results Significantly higher ratio of comfortable feeling,lower ratio of seriously discomfortable feeling were observed in crew and passengers at 200 km/h compared with those at 250 km/h (P＜0.05),as well as rapid disappearance of discomfortable feeling in crew (P＜0.05) and significantly higher ratio of lightly discomfortable feeling and lower ratios of tinnitus and eardrum discomfort induced by air pressure and noise in passengers at 200 km/h.No significant difference was observed in ear discomfort induced by air pressure and noise among crew,and the duration of disappearance of discomfortable feeling among passengers between 200 km/h and 250 km/h.The noise in carriages exceeded the related standard when the high-speed train passing through the tunnels.Conclusion The individuals feel more comfortable at 200 km/h than 250 km/h in this line.,which may be related with rapid variation of wind speed and noise when the train passes through the tunnels with high speed.