NOVELTY - An inverted pyramidal nano-porous surface texture forming method involves selecting silicon as silicon material. The material is cleaned using solvent ultrasonically to remove organic matter residual substance on surface of the silicon wafer. The cleaned material is subjected to chemical corrosion treatment by using hydrogen fluoride and nitric acid mixed solution to remove mechanical damage layer surface of silicon chip to obtain smooth surface multi-crystal silicon wafer. The silicon wafer is soaked in mixed aqueous solution of hydrogen fluoride and silver nitrate.    USE - Method for forming an inverted pyramidal nano-porous surface texture on polysilicon for preparing short wave enhanced type solar cell (claimed).    ADVANTAGE - The method enables forming inverted pyramidal nano-porous surface texture with improved lifetime, low surface reflectivity and high spectral response in a simple, convenient and inexpensive manner.    DETAILED DESCRIPTION - An inverted pyramidal nano-porous surface texture forming method involves selecting silicon as silicon material. The material is cleaned using solvent ultrasonically to remove organic matter residual substance on surface of the silicon wafer. The cleaned material is subjected to chemical corrosion treatment by using hydrogen fluoride and nitric acid mixed solution to remove mechanical damage layer surface of silicon chip to obtain smooth surface multi-crystal silicon wafer. The silicon wafer is soaked in mixed aqueous solution of hydrogen fluoride and silver nitrate at room temperature. The wafer is placed in mixed aqueous solution of hydrogen peroxide and hydrogen fluoride, when nano-sliver grains are deposited on the surface of the silicon wafer. The resultant wafer is subjected to chemical corrosion treatment at the room temperature to form nano-porous black silicon texture on the surface of the silicon wafer. The wafer is soaked in nitric acid solution and washed using de-ionized water to remove redundant nano silver particles to obtain nano porous black silicon sample. The sample is placed in dilute hydrogen fluoride solution to remove oxide layer on the surface of the wafer. The resultant sample is soaked in 0.1-1% sodium hydroxide etching solution to modify the surface of the solution and to carry out reaction for 3-9 minutes at room temperature to form an inverted pyramidal nano-porous surface texture on polysilicon. An INDEPENDENT CLAIM is also included for a method for preparing short wave enhanced type solar cell.