Sr2+-doped alpha-BBO crystals have been grown by Czochralski method. The full-width at half-maximum of (006) rocking curve is as low as 12 arcsec, which demonstrates the high quality of Sr2+-doped alpha-BBO crystal. The results of transmission spectra and birefractive indices show that Sr2+ ions do not affect the optical quality and properties of alpha-BBO. The measurements of DSC-TG and thermal expansion coefficients of Sr2+-doped a-BBO crystal manifest that Sr2+ ions do not influence the thermal properties of alpha-BBO either. (C) 2003 Elsevier B.V. All rights reserved.