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The pure Nb powder, Si powder or Nb₅Si₃ powder were used as raw materials and three kinds of Nb-16Si binary alloys were fabricated by laser melting deposition (LMD) <i>via</i> the method of powder preplaced and coaxial powder feeding, respectively. The microstructure and micro-hardness of these alloys were investigated with SEM, EDS and XRD, etc. The results show that these Nb-16Si alloys prepared by LMD consist of Nb_SS and Nb₃Si phases. The microstructure of these alloys is influenced by the feeding method and chemical state of the raw powder strongly. The Nb-16Si alloy fabricated by powder preplaced method with the pure element powder as raw materials is composed of dendritic primary Nb_SS with the size of 1-5<i>μ</i>m and Nb_SS/Nb₃Si eutectic structure and the Vickers micro-hardness of the alloy is about 773HV. Using the method of dual-channel coaxial powder feeding can make the microstructure of the Nb-16Si alloy finer and more homogeneous. The primary Nb_SS in this alloy is uniformly distributed with nearly equiaxed shape, the average size is only 2<i>μ</i>m and its micro-hardness is increased to 817HV. The microstructure of the Nb-16Si alloy prepared by dual-channel coaxial powder feeding method with pure Nb and Nb₅Si₃ as raw powder exhibits pseudoeutectic structure, the micro-hardness reaches 907HV.