Formability and forming limit diagrams are important parameters in sheet metal forming industry, have been investigated. Before beginning mass production, a series of experiments on sheet specimens are carried out to determine whether the material may be formed to desired shape or whether defects will occur, which areas on blank will be in danger. One method is to use formability curves called the forming limit diagrams. The experimental studies to obtain these curves include a troublesome and costly process. In this study, forming limit curves are determined experimentally for different heat treatment of 7075 aluminum alloy which is an important material for aerospace industry. 7075 aluminum alloy is one of the alloys that heat treatment is the most effective method on their mechanical properties. In the T6 tempered 7075 alloy, which is the most strengthful form of the alloy, the formability of the material is quite poor. For this reason, solution heat treatment was made firstly to the alloy and then artificial aging is applied. Deformation is applied between these two processes. Eventually, the blank is deformed easier and the strength of the alloy is increased.