Positive roles of acidic ZnCl2 molten salt on wet torrefaction and subsequent pyrolysis were investigated in this work. Wet torrefaction pretreatment was carried out in a muffle furnace at pre-set temperature, respectively. Physicochemical properties of pretreated samples showed that acidic ZnCl2 not only removed alkali and alkaline earth metals (AAEMs) more fully but also significantly lowered the temperature during wet torrefaction. It was also found that the quality of pyrolysis products was upgraded further. The higher relative content of levoglucosan (LG) was detected in bio-oil. Meanwhile, bio-char with higher specific surface area seems a suitable feedstock for the preparation of high-grade activated carbon.