Recently, tactile transmission utilizing wearable devices are necessary to support human life or communicating with people in remote locations. One key factor of transmitting tactile sensation is thermal sensation. Flexible thermal devices have been developed, however, precise temperature distribution cannot be reproduced due to the large size and the flexibility of the devices. Therefore, a technique of rendering thermal sensation considering heat propagation is required to obtain the desired temperature distribution. In this paper, a method to control temperature on a curved surface for implementing to wearable devices is proposed. This method can be applied to various shapes of devices because the deformation of a device can be observed by the propagation delay of the heat flow. Experiments are conducted to verify the validity of the proposed method.