A tire HIL simulator is provided which is capable of, in a testing apparatus where a vehicle model is incorporated into a tire testing apparatus, reproducing the behavior of a tire which corresponds to the three-dimensional behavior of a vehicle, even if a three-dimensional vehicle model is used. As a device for resolving this, this tire HIL simulator includes a tire testing apparatus 2 and a controller 3 connected mutually. The tire testing apparatus 2 conducts a running test on a tire 4a using a mimic road surface body 4, and includes a side force measuring device 37 for measuring a tire side force and each actuator which gives a contact load, a side-slip angle and a camber angle, respectively. The controller 3 sets a steering angle and a tire side force from the side force measuring device 37 as an input value and calculates the three-dimensional motion of a vehicle using a vehicle model 5, and based on this calculation result, outputs each command value for the contact load, the side-slip angle and the camber angle to each actuator of the tire testing apparatus 2.