A telescopic vacuum cleaner suction tube (1) having an outer tube (2) and an inner tube (3) with snap-in depressions (7). The inner tube is telescopically arranged in the outer tube. The suction tube also includes an antitwisting mechanism (4d; 16) and an interlocking device with a snap-in element (15) that is disengaged from a snap-in depression (7) by an actuating element (5) situated about diametrically opposite thereof. The interlocking device includes a spring (6) that positively encompasses at least the inner tube (3) and engages the snap-in element (15) into the nearest snap-in depression (7) of the inner tube (3). The interlocking device and telescoping tubes ensure that the tubes are always securely interlocked and able to withstand shock-like compressive forces, namely while simultaneously providing for an ergonomic handling.