Abstract：The article improves Byun's inversion of seismic travel time in transversely isotropic medium in two aspects. First, an initial value is calculated from optimal value (VL)，then used to make least mean square error analysis. Second, in making optimization analysis of the initial value, measure values (or theoretical values calculated using formulas (4) and(10)) are used as real values for fitting, while Byun's method calculates real value from formula (11).Theoretical modeling shows that this method has quite good adaptability，whereas only in the case of weak anisotropic medium, can Byun's method bring quite accurate result.
