The Czochralski growth of Tm:yttrium aluminate (YAP) crystal (10at%) has been presented. The as-grown crystal has been investigated by X-ray diffraction (XRD) method using its powder sample, which showed that only YAP phase existed and there was no TmAlO3 phase in the crystal. The X-ray rocking curve (XRC) of as-grown crystal was determined, the full-width at half-maximum (FWHM) is 31.5". The absorption and fluorescence spectra of Tm:YAP crystal with different Tm concentration were measured. Though the absorption intensity of 10at% Tm:YAP crystal is much bigger, its fluorescence intensity is smaller. Some "hidden defects" like core and growth striations could not be observed with naked eyes and microscope, but they could only be determined by synchrotron radiation white-beam topography (SRWBT) technique. (c) 2006 Elsevier B.V. All rights reserved.