Portable assembly type crane and hoisting method

The invention provides a portable assembly type crane and a hoisting method, and relates to the field of building construction. Comprising a chassis bearing frame body, adjustable supporting legs are arranged at the four corners of the chassis bearing frame body, electric power-assisted wheels are arranged at the rear end of the chassis bearing frame body, and a rotatable bottom support is arranged on the top face of the chassis bearing frame body; a hydraulic telescopic arm, a winch and a weight box are sequentially arranged on the top face of the rotatable bottom support from front to back, and a hydraulic control box and a crane main control table are arranged on one side of the hydraulic telescopic arm and one side of the winch respectively. An adjusting mechanism is arranged at the bottom of the hydraulic telescopic arm and comprises a main adjusting rod and an auxiliary telescopic rod, and the main adjusting rod comprises a cross beam connecting piece, a length adjusting piece and an angle adjusting pie