An oil depot, which is used for accepting, storing and distributing oil, is accident-prone because of the flammability and explosibility characteristics of oil. As research shown most accidents in oil depots are caused by unsafe acts of human. But it is difficult to monitor and trace the operations of employees with traditional management methods. An internet of things based safety management information system for oil depot is introduced in this paper. It has the following unique characteristics: (1) It adopts the IoT technology to monitor the process of the routine works and prevent the violation acts, (2) RFID tags and PDAs are used in permit to work management to assure that the worksite audition is conducted at the site, (3) IoT technology is introduced in the system to ensure the quality of the inspection. The use in two oil depots shows that the management information system can provide firm support for oil depot safety management.