The positioning method of TDOA (Time Differences of Arrival) is applied to the positioning of aircraft in deck landing.Several major kinds of TDOA algorithms are analyzedand the Spherical Intersection (SX) algorithm is chosen based on the practical situation and the limits of shipboard aircraft landing.Considering that SX algorithm has large computation burdenthe equation coefficient matrix may be illconditioned and so onwe propose an algorithm based on linearization equation.By adding a range difference equation on the foundation of SX algorithmthe nonlinear equation is transformed into a linear equation.The simulation results indicate that : compared with SX algorithmthis algorithm has higher accuracy and smaller computation burden.