We consider Bernstein’s inequality for the Riesz derivative of order 0<\alpha<1 of entire functions of exponential type in the uniform norm on the real line. For this operator, the corresponding interpolation formula is obtained; this formula has nonequidistant nodes. Using this formula, the sharp Bernstein inequality is obtained for all 0<\alpha<1; namely, the extremal entire function and the sharp constant are written out.