Hot-wire measurements are reported on the developing turbulent flows subject to plane rate of strain in a rotating 90 deg bend. The cross-section of the bend varies from 100mm × 50mm rectangular shape at the bend inlet gradually to the 50mm × 100mm shape at the bend outlet with remaining a constant area. Data signals from the rotating test section are transmitted through a slip ring to the personal computer which is located at the outside of the rotating disc. 3-dimensional velocity and 6 Reynolds stress components were calculated from the equations which correlate the fluctuating and mean voltage values measured with rotating a slant type hot-wire probe into 6 orientations. The effects of Coriolis and centrifugal forces on the mean motions and turbulence structures are investigated with respect to rotational speed.