This paper presents new educational software named Earthquake Simulator 3D which analyzes three dimensional frame structures under ground motion effect by using OpenSees and visualizes deformed shape of structure during earthquake by using MATLAB. The plan of structure can be created with the interactive drawing screen. Earthquake record and direction can be selected by user in the program. Parameters such as elastic modulus, shear modulus and surcharge loading can also be defined by user. This software may be used to give examples about structural behavior during an earthquake and can be useful for both civil engineering and earthquake engineering students. In addition to transient analysis, modal analysis can be carried out, mode shapes and modal frequencies can be calculated and observed.