Wall plays an important role in building fire. It can be used to block the fire and prevent its propagation. It restricts free air entrainment, heat transfer and radiation from the wall side of fire. In other cases the wall will accelerate fire to spread to ceiling. Experiment research was carried out to study the influence of wall on the shape of flame and temperature distribution. An array of thermocouple is applied to study the temperature distribution along the wall. A large caliber laser Moiré Deflectometry was used to display the flow procedure during the interaction of wall and flame, especially the changing of buoyant plum along the wall. Five cases, in which the plain wall was settled at 0, 5, 10, -5, and -10 degree with the axis of flame respectively, were studied. The distance between wall and flame was also changed in these five cases. The inclination effect of wall exerting on flame was clearly displayed. Influence of wall on the flame persistent zone height is calculated from experiment data in each case.