A dynamic taxi-sharing system and a sharing method thereof. A ride-sharing service provider carries at least one passenger from the first current location to the first travel destination through a route in an area and sends registration information to a service server. A plurality of ride-sharing requests is sent to the service server, and each of the ride-sharing requests comprises the second current location and the second travel destination. The service server divides the area into n by n blocks. A ride-matching module of the service server chooses a destination area in which the first travel destination is a center point and divides the destination area into k by k blocks. According to the registration information and the ride-sharing requests, the ride-matching module matches at least one ride-sharing traveler to the ride-sharing service provider to achieve a goal of fuel-saving and pollution-reducing.