Although many scholars consider that original non-closed and non-symmetric solution for planetary motion equation of general relativity can be used to solve the problem of advance of planetary perihelion, it has some shortcomings really. This paper discusses the closed and symmetric solution for planetary motion equation of general relativity, and that means that general relativity cannot be used to solve the problem of advance of planetary perihelion. Also, if the solution for planetary motion equation of general relativity is unique, then the non-closed and non-symmetric solution including infinite terms should tend to the closed and symmetric solution. According to "partial and temporary unified theory of natural science so far" including all the equations so far related to natural science and its variational principle, the optimization method can be used to reach the optimal approximate closed and symmetric solution for problem of advance of planetary perihelion. On the basis of the closed and symmetric solution, the planetary orbit should be a rotating ellipse or a rotating approximate ellipse; namely the advance of planetary perihelion is the combined result of two motions: the first motion (the elliptical motion decided by law of gravity or the closed and symmetric approximate elliptical motion decided by planetary motion equation of general relativity) creates the perihelion, and the second motion (solar system’s vortex motion) creates the advance of perihelion; while the parameters of advance will be decided by general relativity or accurate astronomical observation. Key words: General relativity, planetary motion equation, closed and symmetric solution, partial and temporary unified theory of natural science so far, variational principle, advance of planetary perihelion, rotating ellipse