A high-throughput optical sectioning imaging method, comprising the following steps: at S1, modulating a light beam into a modulated light beam capable of being focused on a focal plane of an objective lens and being defocused on a defocusing plane of the objective lens; at S2, imaging, by a camera, in different rows of pixels, a same sample under illumination of the modulated light beam to form sample images, wherein the modulated light beam has incompletely identical modulated intensities on the different rows of pixels in a direction along which the different rows of pixels are arrayed, the sample moves in the direction along which the different rows of pixels are arrayed when imaged, and each of the different rows of pixels sequentially forms a plurality of strip image blocks in the direction along which the different rows of pixels are arrayed, the plurality of strip image blocks formed by each of the different rows of pixels are used to be stitched into a corresponding one of the sample images of the same sample and a formula expression of the formed sample image is: I i = I in f i + I out, where I(i) is a sample image formed in an i th row of pixels, f ( i) is a modulation intensity corresponding to the sample image I(i), I in is a focal plane image of the sample image, and I out is a defocusing plane image of the sample image; at S3, obtaining focal plane images of the sample images in the different rows of pixels by demodulating the sample images according to a demodulation algorithm, the focal plane image being an optical sectioning image, and a demodulation formula of the demodulation algorithm being I in = c × | β I 1 - α I 2 |, where α and β are positive integers, c is a constant greater than 0, I 1 is an accumulated sum of sample images acquired in α rows of pixels, and I 2 is an accumulated sum of sample images acquired in β rows of pixels; β × (an accumulated value of modulation intensities corresponding to the sample images in the α rows of pixels) is different from α × (an accumulated value of modulation intensities corresponding to the sample images in the β rows of pixels). at S1, modulating a light beam into a modulated light beam capable of being focused on a focal plane of an objective lens and being defocused on a defocusing plane of the objective lens; at S2, imaging, by a camera, in different rows of pixels, a same sample under illumination of the modulated light beam to form sample images, wherein the modulated light beam has incompletely identical modulated intensities on the different rows of pixels in a direction along which the different rows of pixels are arrayed, the sample moves in the direction along which the different rows of pixels are arrayed when imaged, and each of the different rows of pixels sequentially forms a plurality of strip image blocks in the direction along which the different rows of pixels are arrayed, the plurality of strip image blocks formed by each of the different rows of pixels are used to be stitched into a corresponding one of the sample images of the same sample and a formula expression of the formed sample image is: I i = I in f i + I out, where I(i) is a sample image formed in an i th row of pixels, f ( i) is a modulation intensity corresponding to the sample image I(i), I in is a focal plane image of the sample image, and I out is a defocusing plane image of the sample image; at S3, obtaining focal plane images of the sample images in the different rows of pixels by demodulating the sample images according to a demodulation algorithm, the focal plane image being an optical sectioning image, and a demodulation formula of the demodulation algorithm being I in = c × | β I 1 - α I 2 |, where α and β are positive integers, c is a constant greater than 0, I 1 is an accumulated sum of sample images acquired in α rows of pixels, and I 2 is an accumulated sum of sample images acquired in β rows of pixels; β × (an accumulated value of modulation intensities corresponding to the sample images in the α rows of pixels) is different from α × (an accumulated value of modulation intensities corresponding to the sample images in the β rows of pixels).