To provide a safety device which prevents a maloperation-caused startup accident of an electric tricycle that does not allow a driver to prepare for driving by hearing engine sounds.

In the electric tricycle, under an on-state of a driving switch 124, a control means 114 supplies drive current to a drive motor 116 based on operation of an accelerating means 121 on a right grip on a handle. The tricycle is provided with a mounting detection means 112 which detects the driver's mounting or not mounting on a driver's seat formed on the tricycle. The mounting detection means 112 is a seat-taking switch disposed on the seat, and detects the driver's mounting on the seat to transmit a seat-taking signal S2 to the control means. When the control means detects an AND signal of a drive signal and a seat-taking signal, the control means carries out current supply to the drive motor when the mounting detection means 112 detects the driver's mounting on the seat, while suspends current supply to the drive motor when the mounting detection means 112 detects the driver's not mounting on the seat.