Microstructured silica surfaces were prepared via wet chemical etching by using a physisorbed layer of Au NP as the etchant mask. Here, a comprehensive study on the effect of different etching parameters such as the etching time, NP size, and HF solution concentration was illustrated. Three different surface structures: small pits, elongated pits, and a long array of elongated pits were observed on a substrate masked with Au NPs. The obtained results were compared with that of bare silica. The array of elongated pits was reported with Au NP-mediated etching for the first time. The properties of the fabricated structures were analyzed in terms of transmittance and pit width. With an increase in etching time, transmittance decreased, whereas pit width and surface roughness increased. For the etching with different HF concentrations, transmittance decreased and the pit width and surface roughness increased with HF concentration. Thus fabricated surface structures on silica, with improved scattering properties, could be utilized in different applications. The process can also be extended to other transparent polymer substrates.