The invention discloses a simple two-layer parking device. The device comprises a backboard, a large carrying plate, a small carrying plate, four slide rails, four three-section-type telescopic slidechannels and a control system; when the large carrying plate is in a state of completely stretching out and the small carrying plate is in a state of completely drawing back, gaps between the edge ofthe inner side of the large carrying plate and the edge of the outer side of the small carrying plate are 8-12 mm, and gaps between the edges of the left and right sides of the large carrying plate and the edges of the left and right sides of the small carrying plate are 20-30 mm, so that it is ensured that the large carrying plate or the small carrying plate does not interfere with each other when alternately moving up and down. The simple two-layer parking device only occupies an area about 1.2 times of an area of a parking space of a vehicle, achieves barrier-free parking, and can be installed simply at narrow and piecemeal sites; meanwhile, the condition and requirement for installing sites are low, core devices are all integrated standard components, detaching and installing are veryconvenient, and the device conforms to various sections such as communities. The two-layer parking device is simple in structure and comprises merely two main parts of power and bearing; moreover, thecost of the device is greatly lower than the numerical value, and the price of an actual product is about 15,000 RMB or even less.