The utility model discloses an adjustable convenient water tank cleaning device which comprises a cleaning mechanism, a telescopic adjusting mechanism and a supporting frame
assembly, and the cleaning mechanism is connected with the telescopic adjusting mechanism. The supporting frame
assembly comprises a supporting frame, a group of transverse supporting and adjusting assemblies, a longitudinal supporting and adjusting
assembly and a top frame, the transverse supporting and adjusting assemblies are oppositely arranged above the supporting frame, and the longitudinal supporting and adjusting assembly is arranged between the transverse supporting and adjusting assemblies and movably connected with the transverse supporting and adjusting assemblies; the telescopic adjusting mechanism is arranged on the longitudinal supporting adjusting assembly, the telescopic adjusting mechanism and the longitudinal supporting adjusting assembly are movably connected, and the top frame is arranged above the transverse supporting adjusting assembly and the longitudinal supporting adjusting assembly. According to the cleaning mechanism, the driving arm and the supporting frame assembly of the cleaning mechanism are optimized, so that the water tank can be cleaned, meanwhile, the length, the transverse position and the longitudinal position of the cleaning mechanism can be adjusted, the requirement for cleaning the water tank at all angles can be met, and sanitary dead corners are avoided.