The invention provides a derricking direction-changeable telescopic belt conveying bidirectional loader-unloader and relates to the field of logistics transportation cargo loading and unloading mechanical equipment. The derricking direction-changeable telescopic belt conveying bidirectional loader-unloader comprises a vehicle having bearing and walking functions, a telescopic cross arm having lifting, telescoping and swinging functions, a middle transition conveyor which has a swinging function and is capable of inclined conveying, a first belt conveyor and a second belt conveyor having derricking, swinging and telescoping functions, a metering device having metering, displaying, storing and printing functions, and an operating control system used for complete machine operation of the loader-unloader. The derricking direction-changeable telescopic belt conveying bidirectional loader-unloader has the advantages of simple structure, reliable work, convenient and rapid movement and transfer, and wide operating scope; the derricking direction-changeable telescopic belt conveying bidirectional loader-unloader can reduce manually-assisted carrying, reduce workload, shorten operating time, increase loading and unloading working efficiency, reduce the cost of loading and unloading carrying, improve working environment and work conditions, guarantee economical, rapid, convenient and safe loading and unloading and transportation, allow change of the direction of logistics conveying, and realize forward and reverse loading and unloading, automatic metering statistical analysis, and loading and unloading quantity/weight recording, displaying and storing.