Highly transparent KNN-0.1LB ceramics were fabricated by CSAS and CS method. And the effects of CSAS and CS processes as well as dwell time on the structures and properties of ceramics were systematically studied. The density of the KNN-0.1LB ceramic can be significantly improved by the CSAS process using the alkali metal hydroxide solution as liquid medium. The potassium-rich phase formed during the molding process can inhibit the volatilization of potassium/sodium as well as grain growth, and then improve the properties of the ceramics. Meanwhile, during the process of heat treatment, potassium-rich phase and the alkali metal element introduced by liquid medium can make up for the volatilization of Kþ and Naþ, providing favorable conditions for obtaining highly transparent KNN-0.1LB ceramics. The CSAS-based KNN-0.1LB ceramic sintered at 1050 C with the dwell time of 24 h exhibits excellent optical transmittance of 74% at 900 nm, fine average grain size of 250 nm, high relative density (>98%) and superior dielectric performance Declaration of