This paper outlines our recent study progresses on (K,Na)NbO3-based lead-free piezoelectric ceramics. It has been found in (KxNa1-x)NbO3 ceramics that piezoelectric properties are almost irrelevant to the K/Na ratio within x=0.40 ~ 0.60 and orthorhombic phase possesses the much better piezoelectric temperature stability than tetragonal phase. Similar phenomena are also observed in some (K,Na,Li)(Nb,Ta)O3 ceramics, of which (K0.55Na0.45)0.965Li0.035Nb0.80Ta0.20O3 ceramic shows particularly an outstanding piezoelectric performance with the piezoelectric properties of d33 =262 pC/N, kp=0.53 and k33=0.63 at room temperature and the weak temperature dependence of electromechanical coupling coefficients in the common usage temperature range. Furthermore, we have successfully obtained a remarkably high d33 value of 413 pC/N in (K0.45Na0.55)0.98Li0.02(Nb0.77Ta0.18Sb0.05)O3 ceramic through the conventional solid state reaction process.