The effects of adding BaF2 on the thermodynamic behavior of YBCO precursory powders,melt-textured microstructure and properties of YBCO superconductors have been investigated.The differential thermal analysis(DTA) results showed that the peritectic decomposition and reaction temperature of YBCO precursory powder were lowered when BaF2 is added,but the temperature range for melting texture growth did not significantly change by the addition of BaF2.The microstructures of the doped samples have been observed by scanning electron microscopy(SEM).The results show that the appropriate addition amounts of BaF2 were not affect the microstructure of YBCO and the distribution of Y211 in the matrix.The transition temperature Tc was measured by susceptibility method without obviously decrease for the samples with an addition amount lower than 10wt% of BaF2.