Liquefied petroleum gas (LPG), liquefied natural gas (LNG) and compressed natural gas (CNG) are widely used as alternative fuels for vehicles worldwide. Vehicle exhaust and roadside air samples were collected at Guangzhou, Shenzhen and Chengdu in China, where LPG, LNG and CNG were used as alternative fuels for vehicles, respectively. Emission characteristics, ozone formation potential (OFP) and health risk assessment of NMHCs from conventional and clean alternative fuel vehicle exhausts were discussed to explore the environmental and health impacts of the change of NMHCs caused by the usage of clean alternative fuels for vehicles. Results indicate that fuel types had significant impacts on the compositions of roadside air. The OFP values of total NMHCs in the CNG (2.5 ppmv), LNG (4.7 ppmv) and diesel (4.5 ppmv) vehicle exhausts were much lower than those in the gasoline (94.3 ppmv) and LPG (23.1 ppmv) vehicle exhausts, indicating that the usage of CNG and LNG for vehicles could lead to effectively reduction of O3 formation from vehicle exhausts. Besides, hazard quotient (HQ), hazard index (HI) and cancer risk (Risk) of NMHCs species in the vehicle exhausts were calculated as well. Both HI and Risk of NMHCs species in the exhausts from gasoline powered vehicles were much larger than those from the other four types of vehicles, indicating that the usage of clean alternative fuels had a positive health impact on human beings compared with gasoline as well.