Infield superconducting properties of {(Ag)_x/CUTl-1223};(x = 0, 0.5,1.0.2.0 and 4.0 wt %) nanoparticlessuperconductor composites were investigated under different applied magnetic field up to H = 8 T. The increase in critical temperature {T_c(0)} and decrease in normal state resistivity(p_o) were observed with increasing contents of Ag nanoparticles in CuTl-1223 superconducting matrix. The value of T_c~(onset)(K) remained almost unaffected by applying external magnetic field, but a decreasing trend in T_c(0) was observed by increasing the value of external applied magnetic field. The transition region below T_c~(onset)(K) showed Arrhenius behavior due to thermally activated flow of magnetic vortices. Enhancement in flux flow activation energy(U_o) and suppression in transition width(ΔT) of CuTl-1223 phase with addition of Ag nanoparticles showed the improvement in flux pinning strength of superconductor. (X = 0, 0.5, 1.0.2.0 and 4.0 wt%) nanoparticlessuperconductor composites were investigated under different applied magnetic field up to H = 8 T. The increase in the critical temperature {T_c (0)} and decrease in normal state resistivity (p_o) were observed with increasing contents of Ag nanoparticles in CuTl-1223 superconducting matrix. The value of T_c ~ (onset) (K) remained almost unaffected by applying external magnetic field , but a decreasing trend in T_c (0) was observed by increasing the value of externally applied magnetic field. The transition region below T_c ~ (onset) (K) showed Arrhenius behavior due to thermally activated flow of magnetic vortices. activation energy (U_o) and suppression in transition width (ΔT) of CuTl-1223 phase with addition of Ag nanoparticles showed the improvement in flux pinning strength of superconductor.