Innovation contest has become a practice adopted by many companies to collect new ideas. How to stimulate participation so as to generate numerous ideas of high quality is the key to the success of innovation contest. Using embedded case study method, we analyze and compare the promoting strategies of two units within R&D center of Volvo Car China for an annual innovation contest. It is found that multilevel factors, including contest routine, power base of innovation champions, perception of the importance of contest, knowledge base of members, influenced the champions’ leadership and the ways of idea generation. We find that both units with different promoting strategies successfully completed the task of innovation contest. One unit applied opening inspiration strategy by combining participative leadership and mutli-round brainstorming of interactive group, while the other unit adopted closing convergence strategy by combining directive leadership and brainstorming of nominal groups. The former generated relaxed innovative climate, whereas the latter reinforced competition and efficiency culture. Both units might face different challenges in the long run.