The invention relates to the technical field of visual lenses, in particular to a large-aperture low-distortion fixed-focal-line scanning machine vision lens. The large-aperture low-distortion fixed-focal-line scanning machine vision lens sequentially comprises a first lens having the positive focal power and a meniscus structure, a second lens having the positive focal power and a meniscus structure, a third lens having the positive focal power and a meniscus structure, a fourth lens having a negative focal power and a meniscus structure, a fifth lens having a negative focal power and a meniscus structure, a sixth lens having the positive focal power and a meniscus structure, a seventh lens having the positive focal power and a meniscus structure, an eighth lens having the positive focalpower and a meniscus structure and a diaphragm located between the fourth lens and the fifth lens from the object surface side to the image surface side; the third lens and the fourth lens are glued to form a first lens group having the negative focal power, and the focal length is fU1; the fifth lens and the sixth lens are glued to form a second gluing lens group having the negative focal power,the focal length is fU2, and the following relationships that 0.35<|fU1/f|<0.7, and 0.35<|fU2/f|<0.7 are achieved. The large-aperture low-distortion fixed-focal-line scanning machine vision lens can meet the application requirements of large aperture, low distortion and the short working distance, and the clear aperture of the large-aperture low-distortion fixed-focal-line scanning machine visionlens can be flexibly adjusted.