The invention belongs to the motorcycle part and component technical field and relates to a motorcycle speed measuring device. The motorcycle speed measuring device is characterized in that the motorcycle speed measuring device includes a shell, a shaft sleeve, a magnetic gear, a Hall element and a signal output line which is electrically connected with the Hall element, wherein the magnetic gearsleeves the shaft sleeve, the shell is arranged at outer side the magnetic gear and is fixed onto the shaft sleeve, the Hall element is installed inside the shell and is located at one side of the magnetic gear, the Hall element is connected with the shell through a clamping buckle, and the signal output line is sleeved with a waterproof line slot; and the joint of the waterproof line slot and shell is provided with a waterproof rubber sleeve. The motorcycle speed measuring device of the invention is a non-contact motorcycle speed measuring device and has the advantages of long service life, small measurement error and high reliability.