An aluminum extrusion thin wall section bar is made of more than one flat though channels. The parallel through channels are independently connected through joint section horizontally, forming symmetrical or asymmetric multi through channels formed parallel flow channel. There are at least one coolant and heating agent flow channels with the cross section in any shape inside the through channel. At least part of the flow channels having the shape of round, elliptical, polygonal, wave or random combination of them to suit for varied requirements for coolants or heating agents. The parallel flow channels for coolants or heating agents form the dual flow channel aluminum extrusion thin wall section bar or multi channel aluminum extrusion thin wall section bar. Fins are used to separate the flow channels for coolants or heating agents. It can replace traditional electrolytic copper pipe, reduce energy consumption, environment pollution and improved utilization of resources. It has low recovery cost, with extensive applications.