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The effects of annealing temperature, cooling rate and multiple annealing process on microstructures, tensile properties and corrosion behavior of a new near-α titanium alloy-Ti90 were comparatively investigated.The results show that when specimens were annealed in the two-phase region,as the annealing temperature increased, the deformed structure gradually spheroidized with a decreased fraction of primary α phase (α_p) and an increased fraction of β-transformation structure (β_t), in which the secondary α phase (α_s) precipitated and coarsened gradually. Those changes finally rose up to the reduced strength and improved plasticity. When annealing in single β phase zone, a fine lamellar microstructure was obtained with fairly coarse original β grains, which resulted in a sharp decrease in the plasticity of the alloy. After water cooling, the acicular α′ martensite phase was precipitated inside β grains, which significantly improved the strength while maintaining good plasticity. With multiple annealing, the size of α_p and β_t increased, and α_s coarsened, leading to a simultaneous decrease in the strength and plasticity of the alloy. The polarization curve test results show that Ti90 alloys with four different microstructures all exhibite passivation behavior in 3.5% NaCl solution with low passivation current density, which implicates a good corrosion resistance. The corrosion resistance of different microstructures is in the order of bimodal microstructure > equiaxed microstructure > Lamellar microstructure.