The time bank is considered to be an important operational mechanism for implementing low-cost strategy for the ageing population in China. Taking Guangdong Province as an example，this article conducted in- depth interviews on time banking among older adults in Shenzhen，Guangzhou，Dongguan，Foshan and Huizhou in Guangdong with the purpose sampling method. A total of 50 people were interviewed，and the interview text data were coded and analyzed with the grounded theory. Sixty valid concepts were obtained，from 50 interviews. From these concepts，15 categories are synthesized，and five core categories are abstracted to construct a model of the influence mechanism of older adults’participation willingness in time banking. It was found that the factors affecting the participation willingness of older adults mainly include time banking cognition，personal needs，emotional value，subjective norms，and participation mechanism. Moreover，a cognitive-attitude-demand-participation forms a closed loop，constituting time bank participation mechanism model.