An in-vivo detection apparatus comprising: a detection component, a cable, a main circuit board, a detection circuit board, two auxiliary circuit boards, and an outer tube, wherein the main circuit board is provided with two first edges parallel to each other disposed along a first direction, and a second edge disposed along a second direction; wherein a first conducting material is disposed on a first side surface of the detection circuit board, wherein the detection component is connected to the first side surface of the detection circuit board, wherein a wiring terminal of the detection component is welded to the first conducting material; wherein each of the two auxiliary circuit boards is connected to one of the first edges, wherein a channel for at least a part of an instrument tube to pass through is formed between the two auxiliary circuit boards, and wherein the channel is provided on a side, along a first direction, of the detection component, the main circuit board, and the detection circuit board, wherein the detection component, the main circuit board, the detection circuit board, the two auxiliary circuit boards, and the part of the instrument tube disposed in the channel are all disposed in the outer tube; wherein the outer tube is directly or indirectly connected to a flexible controllable curved tube; and wherein the first direction and the second direction are perpendicular to each other, characterised in that a second conducting material is disposed on a second side surface of the detection circuit board, the second side surface of the detection circuit board is connected to the second edge of the main circuit board, the second conducting material is perpendicularly welded to a conductive portion on a surface of the main circuit board, and the conductive portion is conductively connected to the cable; the first conducting material is conductively connected to the second conducting material. a main circuit board, a detection circuit board, two auxiliary circuit boards, and an outer tube, wherein the main circuit board is provided with two first edges parallel to each other disposed along a first direction, and a second edge disposed along a second direction; wherein a first conducting material is disposed on a first side surface of the detection circuit board, wherein the detection component is connected to the first side surface of the detection circuit board, wherein a wiring terminal of the detection component is welded to the first conducting material; wherein each of the two auxiliary circuit boards is connected to one of the first edges, wherein a channel for at least a part of an instrument tube to pass through is formed between the two auxiliary circuit boards, and wherein the channel is provided on a side, along a first direction, of the detection component, the main circuit board, and the detection circuit board, wherein the detection component, the main circuit board, the detection circuit board, the two auxiliary circuit boards, and the part of the instrument tube disposed in the channel are all disposed in the outer tube; wherein the outer tube is directly or indirectly connected to a flexible controllable curved tube; and wherein the first direction and the second direction are perpendicular to each other, characterised in that a second conducting material is disposed on a second side surface of the detection circuit board, the second side surface of the detection circuit board is connected to the second edge of the main circuit board, the second conducting material is perpendicularly welded to a conductive portion on a surface of the main circuit board, and the conductive portion is conductively connected to the cable; the first conducting material is conductively connected to the second conducting material.