Abstract: To address the problem that amplitude fluctuations are generally ignored and incident shock wave velocity attenuation is not fully considered in the uncertainty evaluation of dynamic pressure measurement in a non-ideal shock tube, thereby leading to unreliable evaluation results, a reliable method for evaluating the measurement uncertainty of dynamic pressure in the non-ideal shock tube was proposed. In this method, the measurement uncertainties of the stable amplitude and the fluctuation amplitude of dynamic pressure were comprehensively considered and analyzed. First, based on the established traceable measurement model for stable amplitude and the distributed incident shock wave velocity measurement scheme, the fitting uncertainty of the incident shock wave velocity attenuation was investigated, together with the influence of the uncertainty introduced by the correlation between the incident shock wave Mach number at the end face and the specific heat ratio of the medium in the driven section. Their standard measurement uncertainties were then reliably evaluated using the GUM method. Then, for the measurement uncertainty of the fluctuation amplitude, the interaction between adjacent data and the dispersion among repeated measurement results were comprehensively considered. The conjugate Bayesian method was introduced to achieve the evaluation of the standard measurement uncertainty of the fluctuation amplitude with time-varying features. Finally, by combining the standard measurement uncertainties of the stable amplitude and the fluctuation amplitude, a reliable evaluation of the measurement uncertainty of dynamic pressure in the non-ideal shock tube was achieved. The experimental results of dynamic pressure measurement in the shock tube show that the Mach number method ignores the fluctuation amplitude and fails to fully consider the influence of incident shock wave velocity attenuation, thus underestimating the dynamic pressure measurement uncertainty. In contrast, the relative uncertainty of dynamic pressure measurement in the non-ideal shock tube obtained by the proposed method is 1.04%, which effectively improves the reliability of the uncertainty evaluation results.