The invention discloses a self-assembly bi-phase composite ceramic powder, which is characterized in that the powder has a molecular formula of Ba(1-x1-x2-x3-ySrx1Cax2Ax3Ry)Ti(1-zMz)O3, wherein, 0<=x1<=0.18, 0.21<=x2<=0.90, 0.0001<=x3<=0.13, 0.0001<=y<=0.05, 0<=z<=0.20; A is a bivalent element of Mg, Pb, Zn, Cu or Cr, R is La, Pr, Nd, Sm, Eu, Gd, Tb, Dy or Er, and M is a quadrivalent element of Zr, Ce, Cu or Sn. The composite ceramic includes two phases, the content of barium in the first phase is larger than the calcium content, and the calcium content in the second phase is larger than the barium content. The ceramic powder has the features of stress luminescence and electroluminescence, and can be used for the stress distribution measurement and adhesive strength measurement of various parts and members and in plane illumination devices. The parts can be luminous when being coated with ceramic powder on surfaces and applied with stress. The luminous intensity of stress luminescence is in direct ratio with the applied stress in the elastic limit.