The invention discloses an unsteady dynamic balance method based on an order domain-holographic spectrum principle, which has the characteristics of capability in processing unsteady signals by utilizing order domain analysis, fewer times of order domain dynamic balance vehicle start and accurate positioning for unbalanced position, speed fluctuation signals or vehicle start-stop signals are utilized to perform dynamic balance through the integration of the order domain analysis and the holographic dynamic balance. The method extends the application scope of the holographic dynamic balance, breaks through the limitation that the holographic dynamic balance only performs dynamic balance under the steady rotating speed; the method can be combined with the modal balance principle to realize the balance of the whole process of starting the vehicle, and can prevent a machine set from staying near to the critical speed for a long time.