Abstract: A theoretical calculation method for stress concentrations in anisot ropic plates with a circular opening was suggested to composite laminates with a circular opening. Based on the classical laminated plate theory，the finite composite laminate with a circular opening was treated as an anisot ropic plate. The anisot ropic plate was equivalently transformed into a single-oriented fibers plate subjected to off-axial loading. The stress concentration factors of composite laminates with a circular opening can be obtained by means of a similar calculation formulas in the single-oriented fibers plate subjected to off-axial loading. Using the derived expressions，the effects of diameter (opening) to width (plate) ratio d/w on the stress concentration were compared and analyzed. The predicted stress concentration factors are verified with finite element simulation and the experimental results.