In order to examine the springback amount and material properties of aluminum alloy sheets (AL1050 and AL5052) in the warm forming which forms the sheet above the room temperature, the stretch bending and draw bending tests and tensile test in various high temperatures are carried out. The warm forming temperature 15$0^{circ}C$ is a transition in terms of the material properties: over the forming temperature 15$0^{circ}C$, them $sigma$$_{YS}$ , $sigma$$_{TS}$ , E, K, n, etc. are bigger but $varepsilon$ and plastic strain ratio are smaller. Below the forming temperature 15$0^{circ}C$, there are no big differences in material properties as the forming temperature changes. AL5052 sheet has more springback effect than AL1050 sheet. While the springbacks of AL5052 and AL1050 sheets show a big reduction over the warm forming temperature 15$0^{circ}C$ in the stretch bending test, the springback rapidly reduces in the warm forming temperature 15$0^{circ}C$-20$0^{circ}C$ for AL5052 sheet and 20$0^{circ}C$-25$0^{circ}C$ for AL1050 sheet in the draw bending test.