The invention relates to a car parking and picking-up method of a three-dimensional parking device by utilizing gear planning structure parking spaces. A carrier frame (4) is used for loading and unloading a vehicle (7), a carrier vertical lifting unit (5) lifts or lays down the carrier frame (4), and a carrier horizontal moving unit (6) enables the carrier frame (4) to move in the horizontal direction on a second-floor parking space (2) or a channel (3) at the top of the second-floor parking space (2). The parking and picking-up method is characterized in that a gear planning structure is installed on each parking space of the second-floor parking space (2), a gear planning structure is installed at the bottom of the carrier frame (4) in a corresponding mode, and vehicle wheels are parked on the gear planning structure; after gear planning of the carrier frame (4) penetrates through a gear planning seam of the second-floor parking space (2), the vehicle (7) is subjected to mutual transferring between the carrier frame (4) and the second-floor parking space (2), and a passing space used for enabling the bottom of the carrier frame (4) to move in the horizontal direction is installed on the position, below the corresponding gear planning structure, of the second-floor parking space (2).