The present invention provides a pretreatment device for improving the uniformity of the etched texturing surfaces of polycrystalline silicon wafers. The device comprises a thermostatic bath containing constant-temperature water and transmission rollers disposed in the thermostatic bath; the transmission rollers are arranged under the constant-temperature water; silicon wafers to be etched are arranged on the transmission rollers; the transmission rollers rotate to drive the silicon wafers to be etched to move; and the device further comprises a constant-temperature air drying mechanism which is communicated with the outlet end of the thermostatic bath. According to the pretreatment device of the invention, the silicon wafers to be etched are kept under 8 to 10 DEG C in advance which is equivalent to the temperature of the etching bath, and therefore, the on-chip uniformity and inter-chip uniformity of the texturing surfaces of the polycrystalline silicon wafers can be greatly improved, the proportion of polycrystalline silicon wafers with color difference in the battery sheets can be decreased, and the qualified rate of the battery sheets can be improved.