An experiment which deals with pressure effects on the output characteristics of a small radial copper vapor laser is described. When the buffer gas pressure is increased from 2.0 kPa to 10.0 kPa, the plasma tube resistance increases. At the optimal pressure about 2.7 kPa, the output power has a maximum. Moreover, following the increasing of the gas pressure, the pulse duration time first decreases and later increases, and the critical pressure is 4.7 kPa. The intensity profile of the laser output shows a lower axial intensity and a higher intensity on the tube wall at the higher pressure.