A micromechanical sensor device is described that includes an integrated housing seal, a micromechanical sensor assembly, and a corresponding manufacturing method. The micromechanical sensor device with an integrated housing seal is equipped with a micromechanical sensor chip that includes an upper side and a lower side, a sensor area that may be brought into contact with an environmental medium being provided on or at the upper side, and is equipped with at least one circumferential trench, open toward the upper side, that is provided in the periphery of the sensor area and that is at least partly filled with a sealing medium for sealing a corresponding area of a housing to be mounted thereon.