Abstract: Considering the inconvenience of combining infinite dynamic elements in frequency domain with those in time domain, a new infinite dynamic element is proposed based on the wave propagation function in time domain. The new infinite dynamic element in time domain is developed in ANSYS with the UPFs tool and registered as an element of ANSYS. At last, the efficiency of the new infinite dynamic element in time domain is verified with a typical example by comparing its results with those produced by far, viscous and elastic-viscous artificial boundary conditions. The verification shows that the new infinite dynamic element proposed in time domain is successful and can be combined with finite element in time domain easily.