An infrared laser-absorption technique for in situ temperature and nitric oxide species sensing in high-temperature gases is presented. A pair of quantum cascade lasers in the mid-infrared near 5 were utilized to probe rovibrational transitions in nitric oxide’s fundamental band. The line parameters of the selected transitions, including line strengths and collision broadening coe ients of nitric oxide with argon and nitrogen, were evaluated during controlled room- temperature static cell experiments and high-temperature shock tube experiments at temperatures between 1000 and 3000 K, and pressures between 1 and 5 atm.