The invention discloses a method for calculating accuracy of a surface antenna single panel and belongs to the technical field of antennas. The method includes the steps of establishing a panel localcoordinate system, establishing a conversion relationship between a measurement coordinate system and the panel local coordinate system, establishing a conversion relationship between the panel localcoordinate system and a theoretical design coordinate system, and calculating the accuracy of the panel and the like. The method can be used for calculating the precision of the panel for measurementor simulation, and the method provides an important guide for theoretical design work and is an important improvement over the prior art.