Ventilation system for a fuel tank of an internal combustion engine

The invention relates to a ventilation system for a fuel tank of an internal combustion engine, the device comprising a filter. The aim of the invention is to functionally improve one such device, simultaneously reducing the structural volume thereof by saving filter volume. To this end, the inventive device is characterized by at least one of the following features: a first stop valve leading to the atmosphere communicates with the same via an air intake filter of the internal combustion engine; and the inner chamber of the tank and the air-guiding region located between the tank and the stop valves are connected to a pump which sucks air from the atmosphere into said region via the air intake filter of the internal combustion engine, if one such pump is available.