The invention provides a probabilistic harmonic analysis method for a distributed photovoltaic access distribution network considering weather scenario. The probabilistic harmonic analysis method comprises the following steps: firstly, obtaining shape parameters for Beta distribution of a distributed photovoltaic system output power curve by using a parameter estimation method in typical weather scenario; determining a probability distribution model of output power of the photovoltaic system and sampling to obtain a distributed photovoltaic output power value; carrying out harmonic power flowcalculation to obtain harmonic injection current of the distribution network and further obtaining harmonic voltage of each node of the system; after all sampling times are finished, obtaining the harmonic voltage probability distribution and harmonic distortion rate THD of the distribution network by calculating.