Tensile failure behavior of ceramic matrix composites (CMCs) was characterized with nondestructive evaluation (NDE) techniques. Prior to the mechanical testing, infrared (IR) thermography was employed to obtain thermal diffusivity maps for CMC specimens. IR thermography also was used for quantitative analyses of the progressive damage and in-situ monitoring of the damage during tensile tests, while ultrasonic (UT) C-scans were used to present defect distributions of the composites. The thermal diffusivity map showed good consistency with ultrasonic C-scan results of CMC specimens. In this investigation, qualitative relationship between UT signatures and thermal diffusivity has been introduced, and the temperature changes of CMC specimens during tensile test have been measured. Moreover, the correlation between NDE results and fracture behavior of CMCs has been presented to understand tension fracture behavior of CMCs.