A new alternative manufacturing method using focused-ion-beam (FIB) technology is introduced in detail in this article. Fabrication of microcylindrical lenses can be realized based on SiO2 deposition and FIB milling. The former is suitable for fabricating directly on the surface of the microdevice. The latter is generally used for milling on chip-integrated microcomponents. The form accuracy can be precisely controlled by varying the parameters, such as the ion dose, accelerating voltage, beam current, etc. We analyzed in detail the influence of implanted Ga+ in the microlens and the precursor partial pressure of H2O and tetramethylcyclotetrasiloxane during the SiO2, microlens deposition on transmission. The experimental results and quality of the microlens using different methods are presented. We conclude that microfabrication of microcylindrical lenses using both FIB milling and deposition is practicable.