It has been found that the as-quenched ribbons of $Sm_{x}Fe_{100-x-y}Ti_{y}(3.8{leq}x{leq}11.5,;3.8{leq}y{leq}19.2)$ are composed of metastable $TbCu_{7}-type$ structure, ${alpha}-(Fe,;Ti),;Fe_{2}Ti$ and an unknown phase accompanying strong diffraction line at $d=2.14{AA}$. The metastable $TbCu_{7}-type$ phase, which was formed by rapid quenching, did not transform fully to the stable phases after annealing at $850^{circ}C$ for 45 minutes except the one existed in $SmFe_{11}Ti$ melt-spun ribbon. The $SmFe_{11}Ti$ melt-spun ribbon, annealed at $850^{circ}C$ for 45 minutes in vacuum, was found to be composed of $ThMn_{12}$. $alpha$-(Fe, Ti) and $Fe_{2}Ti$ phases. The formation of $alpha$-(Fe, Ti) and $Fe_{2}Ti$ phases in this melt-spun ribbon was due to the evaporation of Sm atoms during the high temperature annealing. The atomic ratios for the surface and the inside of $SmFe_{11}Ti$ melt-spun ribbon annealed in vacuum were $SmFe_{25.8}Ti_{2.6}$ and $SmFe_{11.7}Ti_{1.0}$ respectively. It is thought to be that much of $alpha$-(Fe, Ti) and $Fe_{2}Ti$ phases exist on the surface of ribbon.