The utility model relates to a light combined multi-purpose bicycle which has the structure that handle bars are hinged on a bicycle frame close to a saddle, and are connected with a front fork through a wire rope or a drag link. After accessories are added to the utility model, the utility model can be used as side bicycles or is connected in parallel with another bicycle to form a four-wheel funabout. The width of a back fork lever of the bicycle frame can be adjusted. Back wheels are changed into two wheels with adjustable wheelbase, forming a safe and comfortable bicycle for old people. The bicycle is provided with a hitch mechanism; thus, a plurality of bicycles can be connected in series.