This paper aims to analyze the reliability of experimental and analytical methods for predicting the first step of destruction to quantify the uncertainty of models and parameters. For this purpose, the mechanized long-face mining project in Block 3, Parvadeh 4 mine has been selected. In this regard, using two first-order second moment (FOSM) and Monte Carlo simulation (MCS) methods, the reliability of the two experimental methods RQI and CMRI and the analytical model based on beam mechanics have been analyzed by determining the reliability index (β). The findings showed that the results of the two methods FOSM and MCS are close. Also, the reliability index of the RQI model (average 23.92) is more than the other two methods, followed by the analytical model (average 21.17) and the CMRI model (average 9.71), respectively. Analysis of these results shows that the small difference in the reliability index of the RQI method and the analytical model can be justified by considering the greater number of parameters involved in the analytical model. On the other hand, the average value of the predicted degradation step of the two analytical methods (average 20.03) and CMRI (average 19.17) is close to each other and is acceptable based on past experiences in the Parvadeh area. Based on these two issues, the analytical model is the most reliable model for predicting the first degradation step in the Parvadeh 4 Block 3 mine.