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In this paper a low temperature metallization i.e. standardization of electroless Ni plating on alumina ceramic is summarized. It includes three main steps (i) pre-treatment, (ii) activation and (iii) Ni plating. Pre-treatment includes degreasing with non-silicate soap solution followed by ultrasonic cleaning in acetone and etching the alumina surface to generate roughness for making it suitable for adhesion. Etching has been obtained by immersion in 10% NaOH at 50°C for 10 minutes and 50% HF for 15 minutes at room temperature. Activation of the surface is the most important step before electroless plating on alumina ceramic. Activation has been achieved with Ginplate 442 (commercial chemical) by immersing the alumina specimen for 5 minutes at room temperature. Activated alumina samples have been used for electroless Ni plating in Ginplate 418 bath at 88°C.Uniform, densely compact coating has been achieved as revealed by SEM image. XRD plot confirms the presence of metallic nickel together with phases of Ni 2 P, NiP, Ni 3 P confirming the nickel phosphite based plating. Subsequently, tube to tube joining of these metallized alumina ceramic tubes has been conducted through vacuum brazing process with copper silver eutectic alloy (28Cu-72Ag) whose cross section showed good joint with excellent wettability of Cu-Ag with Ni plating.