Motorcycle helmet wearing rates remain low in smaller cities in developing countries. We therefore examined the knowledge, attitudes, and behavior of motorcyclists towards helmet use in two mid-sized cities in China. The methods included roadside observation and interview. Observational sites were randomly selected from main roads and secondary streets; all motorcycles passing by were observed. Riders near the sites were opportunistically approached and asked about knowledge of and perceptions about helmet use. Altogether, 75,949 drivers and 17,230 passengers were observed. A large proportion of both drivers and passengers (34% and 71%, respectively) did not wear a helmet, or did not have their helmet fastened (34% and 14%). Proper helmet usage rates were lower among male drivers, younger people, on secondary streets, and during the evenings and weekends. The majority of the 2325 drivers interviewed (90%) acknowledged the benefits of helmet wearing, but 72% reported that helmets are not always comfortable, and only 20% said they would wear a helmet for preventive purposes. Furthermore, many felt that police enforcement was not strict (62%). These results suggest that educational programs about helmet use in provincial China should emphasize the risks of improper use. Strict enforcement, especially on secondary roads and during non-peak hours, could also improve helmet usage.