A single-body typed TDLAS sensor was developed, and its robustness and performance were experimentally evaluated under harsh thermal and mechanical environments which could be formed in scramjet intake. To confirm integrity and operability of the TDLAS sensor in the harsh thermal environments, high-thermal gradient, long-duration heating, and aero-heating tests were conducted. The high-thermal gradient, long-duration heating, and aero-heating tests were performed using high-temperature torch, furnace, and supersonic wind tunnel, respectively. In addition, vibration, mechanical shock, and acceleration tests were performed to analyze the durability and operating performance of the TDLAS sensor in the harsh mechanical environments. The vibration/mechanical shock, and acceleration tests were carried out using shaker and centrifuge, respectively. The TDLAS sensor did not experience any damage and had a stability of signal measurement under these severe thermal and mechanical environments. The experimental test results showed that the single-body TDLAS sensor in this paper could be used in the extreme thermal and mechanical conditions which could be formed in the scramjet intake.