To make it possible to cool an electronic equipment main body and an extension electronic equipment with one cooling fan at a low cost, with a small configuration and at low noise by cooling the function extension equipment with the cooling fan of an electronic equipment main body in a state where the function extension equipment is attached to the electronic equipment main body.

A docking mechanism is provided for a notebook-type personal computer 1 and a docking station 2 and they are connected and separated with a simple operation. The cooling fan 15 is provided near the trailing end of the notebook-type personal compute 1. Projection parts 5a and 5c are provided inside an exhaust duct 5 and a through hole 5b from the inner part of the docking station is made for the projection part 5a. When the cooling fan 15 is driven, the inner air of the notebook-type personal computer 1 is exhausted and it passes through the inner part of the exhaust duct 5. At that time, the projection parts 5a and 5c narrow exhaust air and negative pressure is generated. The inner air of the docking station 2 is sucked from the hole 5b to radiate the heat in the decking station 2.