A built-in micro interfacial enhanced reaction system for terephthalic acid production with p-xylene comprising: a reactor and a micro interfacial unit disposed inside the reactor; the reactor comprises a shell, an inner cylinder concentrically disposed inside the shell, and a circulating heat exchanger partially disposed outside the shell, the inner cylinder having a bottom end connected to an inner bottom surface of the shell in a closed manner and a top end extending toward a top end of the reactor, a region between the shell and the inner cylinder being a first reaction zone, the inner cylinder containing a second reaction zone and a third reaction zone from top to bottom, the circulating heat exchanger being connected to the inner cylinder and the micro interfacial unit respectively by connecting the circulating heat exchanger and a pressure pump through a pipe; the micro interfacial unit comprises a plurality of first micro interfacial generators and a second micro interfacial generator, wherein each of the plurality of first micro interfacial generators is respectively disposed at bottom portions of the first reaction zone, the second reaction zone and the third reaction zone for breaking air as a reaction raw material into micro-bubbles with a diameter greater than or equal to 1 μm and less than 1 mm, and the second micro interfacial generator is disposed at an upper end of the second reaction zone and opposite to the first micro interfacial generator disposed at the bottom portion of the second reaction zone for entraining unreacted air collected at a top portion of the reactor into an interior and breaking into the micro-bubbles under power of a reaction liquid inside the second reaction zone transported by the circulating heat exchanger; characterized in that: wherein a height of the inner cylinder is 4/5 of a height of the shell; wherein a wave protection grid is provided between the second reaction zone and the third reaction zone; wherein a volume of the first reaction zone accounts for 45% of a total reaction volume in the reactor, a volume of the second reaction zone accounts for 53.5% of a total reaction volume in the reactor, and a volume of the third reaction zone accounts for 1.5% of a total reaction volume in the reactor. the reactor comprises a shell, an inner cylinder concentrically disposed inside the shell, and a circulating heat exchanger partially disposed outside the shell, the inner cylinder having a bottom end connected to an inner bottom surface of the shell in a closed manner and a top end extending toward a top end of the reactor, a region between the shell and the inner cylinder being a first reaction zone, the inner cylinder containing a second reaction zone and a third reaction zone from top to bottom, the circulating heat exchanger being connected to the inner cylinder and the micro interfacial unit respectively by connecting the circulating heat exchanger and a pressure pump through a pipe; the micro interfacial unit comprises a plurality of first micro interfacial generators and a second micro interfacial generator, wherein each of the plurality of first micro interfacial generators is respectively disposed at bottom portions of the first reaction zone, the second reaction zone and the third reaction zone for breaking air as a reaction raw material into micro-bubbles with a diameter greater than or equal to 1 μm and less than 1 mm, and the second micro interfacial generator is disposed at an upper end of the second reaction zone and opposite to the first micro interfacial generator disposed at the bottom portion of the second reaction zone for entraining unreacted air collected at a top portion of the reactor into an interior and breaking into the micro-bubbles under power of a reaction liquid inside the second reaction zone transported by the circulating heat exchanger; characterized in that: wherein a height of the inner cylinder is 4/5 of a height of the shell; wherein a wave protection grid is provided between the second reaction zone and the third reaction zone; wherein a volume of the first reaction zone accounts for 45% of a total reaction volume in the reactor, a volume of the second reaction zone accounts for 53.5% of a total reaction volume in the reactor, and a volume of the third reaction zone accounts for 1.5% of a total reaction volume in the reactor. wherein a height of the inner cylinder is 4/5 of a height of the shell; wherein a wave protection grid is provided between the second reaction zone and the third reaction zone; wherein a volume of the first reaction zone accounts for 45% of a total reaction volume in the reactor, a volume of the second reaction zone accounts for 53.5% of a total reaction volume in the reactor, and a volume of the third reaction zone accounts for 1.5% of a total reaction volume in the reactor.