Yukawa Coupling Unification in SO(10) Supersymmetric Grand Unified Theories

We report on a preferred region of supersymmetric parameter space by t, b, tau Yukawa unification. We find a narrow region survives for mu > 0 (suggested by b --> s gamma and the anomalous magnetic moment of the muon) with A_0 \sim - 2 m_{16}, m_{16} > 1200 GeV, mu, M_{1/2} << m_{16} and tan \beta \sim 50 \pm 2. Demanding Yukawa unification thus makes definite predictions for Higgs and sparticle masses.