We synthesized nonmagnetic PtBi2 single crystals and observed a giant linear magneto-resistance (MR) up to 684% under a magnetic field μ0H =15 T at T = 2 K. The linear MR decreases with increasing temperature, but it is still as large as 61% under μ0H of 15 T at room temperature. Such a giant linear MR is unlikely to be described by the quantum model as the quantum condition is not satisfied. Instead, we found that the slope of MR scales with the Hall mobility, and it can be well explained by a classical disorder model. [ABSTRACT FROM AUTHOR]