In this paper，we try to change the material composition and renovate preparation technigues in order to improve critical electric current density（Jc）of high temperature superconductor. Based on 10g 123 phase normal proportion，BaCO₃ from 5mg to 10mg are added respectively. AII sampIes are prepared by solid state reaction method. From the superconductor transit temperature（Tc），transit width ΔT，critical electric current density Jc，SEM and XRD chart，we can draw the conclusion that Tc of abundant 123 phase samples is above 90K（ΔT=1～3K）；20mg BaCO₃ is propitious to growth of 123 phase；some abundant BaCO₃ help to improve Jc.