The invention relates to a push-scan type optical remote sensing load original image bad line automatic detection method and system. The method comprises the following steps: reading an original image to be detected; setting an initial effective column of the original image, and by taking the initial valid column as a reference column, simultaneously scanning the two sides of the reference column; calculating a difference of a normalization exponent between a current column and the reference column in the scanning process, and comparing absolute value of the difference with a threshold T; if the absolute value of the difference is greater than the threshold T, marking that the current column is an invalid column; otherwise, marking that the current column is a valid column, taking the current column as a reference column of a next comparison process, and repeating the step until all columns are marked; and counting the quantity n of all invalid columns, and taking a ratio of the quantity n of all the invalid columns to the total quantity number N of the original image as a bad line rate. According to the method and system provided by the invention, bad lines in the original image in an optical remote sensing load in-orbit operation process can be automatically detected.