Texturing of multicrystalline silicon were prepared by isotropic acidic etching. The mixtures contained hydrofluoric acid(HF) and nitric acid(HNO3), with NaH2PO4.2H2O solution added as diluents. Texturing of multicrystalline silicon were analyzed by SEM, AFM and ultraviolet spectrophotometer, and the mechanism of silicon etching was preliminary discussed. The results show that the surface of multicrystalline silicon being etched has uniform etched-pits and efficient light trapping with NaH2PO4.2H2O solution added as diluents in HNO3/HF mixture. Optimized the conditions, etching rate can control about 2 μm/min, and it meets requirement for industrial production. In HF-rich HF/HNO3 mixtures the surface of multicrystalline silicon easily form etched-pits with sharp edges, more or less small hole，and the lowest reflectance can reach 16.5%～17.5％. In HNO3-rich HF/HNO3 mixtures the surface of multicrystalline silicon form shallower etch pits, larger size bubble-like texture or polished Si wafers and the higher reflectance.