The current situation of on-street scooter and bicycle parking in urban areas in Taiwan has led to the destruction of urban landscapes and the risks of road and pedestrian traffic, which need to be improved by effective parking policy intervention. Therefore, this study from a psycho-cognitive perspective, using empirical data collected from the questionnaire interviews with a systematic random sampling in the field, investigated the psycho-cognitive structure of scooter and bicycle users. In addition, locating the current parking situation as the problem of social dilemmas, this study considered the heterogeneity of awareness of social dilemmas across the users (insensible or sensible of social dilemmas) to reveal the types of parking policy supported by the psycho-cognitive structures in the different states of the awareness. The results indicated that, for the users insensible of social dilemmas, their perceived current parking situation did not influence the parking decision-making, in which their accepted policy was prohibition of parking plus crackdown on offenders; and differently that, for the users sensible of social dilemmas, the more understanding of current parking situation they had, the higher degree to which they considered in parking decision-making, in turn positively influencing the acceptability of parking lot addition and education plus persuasion.