A pedestrian collision detection apparatus includes a bumper sensor, an acceleration sensor, a vehicle speed sensor, and a controller. The controller calculates an effective mass based on outputs from the bumper sensor and the speed sensor. The controller calculates a velocity change based on an output from the acceleration sensor. Further, the controller includes a two-dimensional map, which contains an effective mass and a velocity change and defines a pedestrian area for collision with a pedestrian. The controller determines a collision with a pedestrian when the pedestrian area contains a point determined by the calculated maximum effective mass and maximum velocity change. It is therefore possible to accurately distinguish a collision between the vehicle and the pedestrian from collision with the other object to reliably detect the collision.