In this study, In order to improve dielectric and piezoelectric properties of Lead-free piezoelectric ceramics, $0.95(K_{0.5}Na_{0.5})NbO_3-0.05Li(Sb_{0.8}Nb_{0.2})O_3+0.2;wt%Ag_2O+0.4;wt%MnO_2+Xwt%CuO$ were investigated as a function of the amount of CuO addition. With increasing the amount of CuO addition, density was increased up to 0.4 wt.% CuO and then decreased above. And also, electro mechanical coupling factor ($k_p$) was decreased. At the 0.4 wt% CuO added specimen sintered at $1020^{circ}C$, $k_p$, Qm, density, dielectric constant (${varepsilon}_r$) and $d_{33}$[pC/N] showed the optimal value of $4.37;g/cm^3$, 0.354, 305, 645, and 144 pC/N respectively.