In this study, we use the commercial simulation software, DIMOS2.0, to study improvement of viewing angle performance. Based on concepts of optical phase compensation, optimized conditions of composite uniaxial compensation films are achieved in optically compensated bend (OCB) liquid crystal displays (LCDs). In conditions of D65 illumination for compensated cells, it shows that viewing angles with contrast ratio over 10 are in the ranges of horizontal 100 degrees and perpendicular 130 degrees. No gray scale inversion occurs within polar angle of 70 degrees at horizontal direction. According to definition of CIE 1931, color coordinate of white point in non-compensated and compensated simulated cells are (0.29634, 0.32592) and (0.27143, 0.29306) at on-axis viewing direction, respectively. Contrast ratio is over 3000 at on-axis viewing direction.