Truck drivers is a key group to promote road safety. For them, proper priority ranking scheme of content adaptation design benefits the high system effectiveness of in-vehicle driver decision support. Taking Chinese truck drivers as an example, the present study revealed the context-adaptive support information from the perspective of truck drivers; their perceptions of in-vehicle information contents priority in 6 typical driving contexts. Data of 19 participants from 7 logistics companies were collected using a simulation interview method. Based on qualitative summary and statistical analysis, the results are summarized in two aspects; contextual information priority and impacts of driving experience on it. From the perspective of truck driver requirement, these results provide references for the design of context-adaptive driver decision support.