In this study a sharing vehicle platform was proposed by using smart contract on Blockchain environment. Through the combination of the smart contract of Blockchain and the Internet of Vehicles, the transfer and record of vehicle driving privileges could be realized. And the privileges could be effectively removed after the vehicle completed the task of transportation to ensure the privileges were not misused or abused. To effectively implement the authorization and operation of the shared Emergency Cars (ECs), a Priority Passing Smart Contract (PPSC) flow framework was proposed also. It is an authorization authentication method based on the smart contract. The PPSC flow consists of two main parts: vehicle rescue and authorization-planning-broadcasting. These processes run on Blockchain environment to support the whole platform for the shared ECs.