We report X-ray diffraction measurements of the charge-ordered organic conductor theta-(BEDT-TTF)(2)CsZn(SCN)(4) at various temperatures with external currents. The two kinds of diffuse scattering observed at q(1) = (2/3 k 1/3) and q(2) = (0 k 1/2) exhibit remarkable difference in the interplane correlation along the b-axis, the temperature dependence, and the electric-current dependence. These observations suggest that the two diffuse scatterings come from spatially different charge-ordered domains. The external current melts the q(2)-type domains, which can control the competition of the two orders. Copyright (C) EPLA, 2008