Tyre pressure regulating device (1.1, 1.2, 1.3, 1.4, 1.5), by means of which the tyre pressures of the vehicle wheels (5, 6, 7, 8) of a plurality of vehicle axles (3, 4) of a motor vehicle with pneumatic tyres can be adjusted while driving, having the following features: - at least one switchover valve (10, 11; 11'; 60), which is arranged on the vehicle chassis, can be controlled in an electromagnetic/pneumatic manner, and by means of which at least one main connecting line (25, 26), which leads to an axle valve (12, 13) of a vehicle axle (3, 4), can alternately be connected to a pressure-carrying filling pressure line or to an unpressurized vent line, - an axle valve (12, 13), which is arranged on the vehicle chassis for each vehicle axle (3, 4), can be controlled in an electromagnetic/pneumatic manner, and by means of which an axle connecting line (27, 28), which branches into outer wheel connecting lines (29, 30, 31, 32) of the relevant vehicle axle (3, 4), can alternately be connected to the respective main connecting line (25, 26) or can be shut off with respect to the latter, characterized by - a pressure-controlled wheel valve (14, 15, 16, 17), which is arranged at each vehicle wheel (5, 6, 7, 8) and by means of which an inner wheel connecting line (37, 38, 39, 40), which leads into the interior of the relevant wheel tyre, can alternately be connected to the associated outer wheel connecting line (29, 30, 31, 32) or can be shut off with respect to the latter, - a pilot control valve, which is arranged on the vehicle chassis, can be controlled in a purely electromagnetic manner or in an electromagnetic/pneumatic manner, and by means of which a main control line (44, 46), which branches into axle control lines (47, 48) of the vehicle axles (3, 4), can alternately be connected to a pressure-carrying control pressure line or to a vent outlet, - two-channel rotary couplings (33, 34, 35, 36), which are arranged between the vehicle axles (3, 4) and the associated vehicle wheels (5, 6, 7, 8), are provided with switchable seals, and via which the compressed air which is carried in the outer wheel connecting lines (29, 30, 31, 32) and the control pressure medium which is carried in wheel control lines (49, 50, 51, 52), which branch off from the respective axle control line (47, 48), are transferred in a pressure-tight manner. - at least one switchover valve (10, 11; 11'; 60), which is arranged on the vehicle chassis, can be controlled in an electromagnetic/pneumatic manner, and by means of which at least one main connecting line (25, 26), which leads to an axle valve (12, 13) of a vehicle axle (3, 4), can alternately be connected to a pressure-carrying filling pressure line or to an unpressurized vent line, - an axle valve (12, 13), which is arranged on the vehicle chassis for each vehicle axle (3, 4), can be controlled in an electromagnetic/pneumatic manner, and by means of which an axle connecting line (27, 28), which branches into outer wheel connecting lines (29, 30, 31, 32) of the relevant vehicle axle (3, 4), can alternately be connected to the respective main connecting line (25, 26) or can be shut off with respect to the latter, characterized by - a pressure-controlled wheel valve (14, 15, 16, 17), which is arranged at each vehicle wheel (5, 6, 7, 8) and by means of which an inner wheel connecting line (37, 38, 39, 40), which leads into the interior of the relevant wheel tyre, can alternately be connected to the associated outer wheel connecting line (29, 30, 31, 32) or can be shut off with respect to the latter, - a pilot control valve, which is arranged on the vehicle chassis, can be controlled in a purely electromagnetic manner or in an electromagnetic/pneumatic manner, and by means of which a main control line (44, 46), which branches into axle control lines (47, 48) of the vehicle axles (3, 4), can alternately be connected to a pressure-carrying control pressure line or to a vent outlet, - two-channel rotary couplings (33, 34, 35, 36), which are arranged between the vehicle axles (3, 4) and the associated vehicle wheels (5, 6, 7, 8), are provided with switchable seals, and via which the compressed air which is carried in the outer wheel connecting lines (29, 30, 31, 32) and the control pressure medium which is carried in wheel control lines (49, 50, 51, 52), which branch off from the respective axle control line (47, 48), are transferred in a pressure-tight manner.