The invention discloses a method for self-adaptive weight grooming of a dynamic service flow in an optical network. Through the reasonable arrangement of the optical path weight, the problem that the resource use rate is low due to the fact that a newly-established optical path is insufficiently considered in an existing method is solved. The method for self-adaptive weight grooming of the dynamic service flow in the optical network mainly comprises the steps that firstly, network topological information and initial resource allocation information are input and an event list is initialized according to information of dynamically-arrived services; then events in the event list are processed in sequence; if the events are arrival events, the optical path weight is updated, shortest paths are selected for the services corresponding to the arrival events, and network resources and the event list are updated; if the events are departure events, the network resources and the event list are updated; event processing operation is repeated until the whole event list is completely processed. According to the method for self-adaptive weight grooming of the dynamic service flow in the optical network, the grooming paths can be selected for the services in a self-adaptive mode and load balance and efficient resource utilization are achieved.