As a special kind of spectrometer with the Czerny-Turner structure, the echelle spectrometer features two-dimensional dispersion, which leads to a complex astigmatic condition. In this work, we propose an optical design of
astigmatism-corrected echelle spectrometer using an off-the-shelf cylindrical lens. The mathematical model considering
astigmatism introduced by the off-axis mirrors, the echelle grating, and the prism is established. Our
solution features simplified calculation and low-cost construction, which is capable of overall compensation of the
astigmatism in a wide spectral range (200-600 nm). An optical simulation utilizing ZEMAX software,
astigmatism assessment based on Zernike polynomials, and an instrument experiment is implemented to validate the effect of
astigmatism correction. The results demonstrated that
astigmatism of the echelle spectrometer was corrected to a large extent, and high spectral resolution better than 0.1 nm was achieved.