Abstract: We study the pairing symmetry in high-temperature superconductors from the point of view of group theory analysis in the framework of Ginzburg-Landau model. By considering an orthorhombic distortion from C4v point group because of the correlation of intralayers, the two apparent transitions needed in earlier work on mixed s and d state have been removed. The structure of a single vortex is presented by solving the Ginzburg-Landau wave function equations of the mixed s±idx2-y2 state. The analysis of the magnetic field dependence of the transport behaviors including the critical current and the R-T curve expansion reveals the origin of the so-called “eigen-pinning effect” and offers a good interpretation of the experimental observations.