Crop fertilizing device

A crop fertilizing device comprises a control device, swing devices and distance adjusting devices, the upper portion of the control device is fixedly connected with the two distance adjusting devices, the lower portion of each distance adjusting device is connected with a set of swing devices connected with the control device, and the control device provides power for the swing devices. The distance adjusting device adjusts the distance between the set of swing devices to adapt to the row spacing of crops, the swing devices drive the spraying heads to stretch between the crops to move up and down in a circulating mode and swing back and forth in a circulating mode, the spraying heads moving up and down cover the crops within the depth range, and the spraying heads swinging back and forth cover the crops in the longitudinal direction. The spraying heads circularly extend into crops from top to bottom and from front to back to spray leaf fertilizer on the crops, the leaf fertilizer covers the whole crops from