Using ethanol as the solvent, oxides and carbonates as starting materials, the nano powders and lead free piezoelectric ceramics of Bi0.5(Na0.7K0.2Li0.1)TiO3(BNKLT) were prepared by Sol Gel method. Using the IR,TG DSC,XRD,SEM and so on,the influence of process parameters on the nano powders and lead free piezoelectric ceramics by ethanol based Sol Gel method were studied. Experimental results showed that the stable,clear, transparent sol can be prepared when the stoichiometry of acetylacetone and tetrabutyl titanate is (N)≥1.0, the reaction temperature≥60 ℃ and pH=2.0~2.5. The BNKLT nano powders with pure perovskite structure were prepared at 600 ℃, and the grain size of powders was about 20 nm, and the dense ceramics of BNKLT were sintered at 1 050 ℃. Performance tests showed that piezoelectric ceramics were prepared by this method which have excellent electrical properties of d33=192 pC/N,kp=0.32,εr =1 096, tan δ=0.039,Qm=79.