Impregnated poly-p-phenylenebenzobisthiazole（PBO） multifilament was manufactured by soaking resin preparation and sample design.Chemical properties of PBO fiber and soaking resin were characterized by X-ray photoelectron spectroscopy (XPS).Differential scanning calorimeter (DSC) was used to analyze curing reaction and kinetics of soaking resin.Dynamic mechanical analysis (DMA) was chosen to characterize resin thermostability. PBO surface and multifilament fracture were observed by scanning electron microscopy (SEM).In addition,casting analysis was used to characterize mechanical properties of soaking resin,and the reliability of multifilament was also indicated by tensile analysis.The results show that the soaking resin is a high matching recipe with uniform infiltration and long storage life for PBO multifilament,which has firm tip reinforcement and short preparation period. The tensile data of multifilament has low volatility,and strength dispersion is under 3%.This would not only improve the reliability and stability of mechanical test,but also increase the efficiency of sample preparation.