Waviness error is one of the most critical errors in the large aspheric lenses grinding and one that has a strong impact on the performance of the optical system. In this article, the waviness error of large axisymmetric aspheric lenses for X-axis direction as well as Z-axis direction is analyzed by employing grate parallel grinding method. The grinding wheel vibration and Z-axis interpolation pace are regarded as the main causes of the surface waviness error. Furthermore, to reduce the waviness error, the influence of grinding parameters on waviness error is investigated. The waviness errors measured during grinding experiments are in good agreement with the theoretical results and the appropriate grinding parameters are recommended.