A modular respiration system is provided for the mechanical respiration of a patient. The respirator system has a modular respiration module (1) for connection to the patient (20), wherein the respiration module (1) contains a respiration system (30) with a respiration drive (3), an electric energy unit (5) and a memory with a control unit (ES II). One or more stationary parts (2) are provided for detachably accommodating the complementary modular respiration module (1). At least one detachable connection interface (8) is provided for data, electric energy and breathing gas exchange between the respiration module (1) and the stationary part or parts (2) accommodating the respiration module (1).