The effect of initial bubble conditions on the motion of a gas bubble rising in viscous liquids was investigated by 3D-computations. Then, a coupled level set/volume-of-fluid (CLSVOF) method was used as a numerical method. For high Eotvos and very low Morton numbers regions predicting a 3D "spherical-cap" bubble, it was computationally demonstrated that the resulting final state of bubbles depended on initial bubble conditions; bubbles with break-up at the center or "spherical-cap" bubbles depending on initial bubble conditions were reproduced. On the other hand, we showed for low Eo and high M conditions that initial bubble conditions did not affect the terminal state of bubble rising motion.