The invention relates to an easy membrane formation type circulating bio-contact oxidation integrated reactor which effectively solves the problems of low possibility of membrane formation of filler, inconvenience for mounting, dismounting and maintenance and poor sewage treatment effect. Guide walls are arranged above a base at the bottom in a pool body; water body circulating gaps are formed between every adjacent two rows of the guide walls; an aerator is mounted in each water body circulating gap; a supporting table is mounted on the circumferential wall of the pool body; a filler frame forming a gap with the inner wall of the pool body is arranged on the supporting table; vertical connecting rods are uniformly distributed in the filler frame; two fillers are connected in series onto the vertical connecting rods; a water inlet pipe and an aerator pipe are arranged at the bottom of the pool body from the top of the pool body; the lower end of the aerator pipe is communicated with the aerator; a water outlet is formed in one side at the top of the pool body; the water outlet is communicated with a water outlet groove; a blow-down pipe is arranged at the bottom of the pool body. According to the integrated reactor, the membrane formation speed is increased, so that sewage can be purified; due to the filler frame, the overhauling operation is simple, convenient, time-saving and labor-saving.