The invention provides a photovoltaic power prediction method based on a ground-based cloud chart. The method comprises the following steps: 1) pre-estimating the movement of a cloud cluster; 2) predicting irradiance on the ground; 3) establishing a comprehensive photoelectric conversion model; 4) and carrying out photovoltaic power prediction. A plurality of digital picture processing techniques are comprehensively applied, so that requirements of problems are highlighted, pertinency and practicality are high, and combined with the traditional statistical method, the photovoltaic power prediction method provides effective technical support and method reference for a photovoltaic power refinement prediction; models are established with multi-steps based on synthesizing of multi-factors; key links in the photovoltaic prediction field are all included in the description of the method, so that universality and robustness are high; in order to combine concrete scenes and application objects used during usage, adjustment parameters are reserved in some links, so that operation is convenient and prediction effect is guaranteed.