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In order to obtain the material properties of reinforcing steel rebar (rebar), tensile test must be performed in the laboratory. Some standards, such as SNI and ASTM, standardize condition of the sample and the loading rate of tensile test. ASTM E8M regulates the loading application (1.15-11.5 MPa/s) of steel rebar test under tension to determine yield properties and SNI 07-2529-1991 regulates 10 MPa/s as the maximum loading rate. These circumstances affect the duration of tensile test in real condition, which may lead to one hour of tensile test. In this article, effect of loading rate of pre-conditioned steel bars (by reducing the section, grinding, and/or lathe according to SNI 07-2529-1991) is investigated using deformed bars (BJTS 40, certified by industries). Random sample of steel reinforcement bars are tested under three different loading rate application. The result of material properties of the rebar, such as stress-strain curve, yield strength, and ultimate strength, are discussed and analysed in this study. Different speed test resulting in different stress rate before yield. However, the stress-strain responses of specimens in the range of linear elastic material are similar. Moreover, at the post yield (plastic) region, the loading rate significantly affected the ductility of the material.