Objective: To explore the relationship between the “white line” of the posterior pharyngeal wall and laryngopharyngeal reflux disease (LPRD). Methods: The subjects were examined by fiberlaryngoscopy, and RSI and RFS scores were performed. The posterior pharyngeal wall was observed to determine the “white line”, the mucosal boundary between the nasopharynx and oropharynx. Results: There was a significant difference in RFS values of the three types of white lines (P = 0.017), and the significant difference was between type I and III (P = 0.006). Age, gender, RSI, and RFS were included to construct the ordered multi-classification logistics regression equation. The effect of RFS on the white line was statistically significant (OR = 0.8, 95%CI −0.326～−0.053, P = 0.008). Conclusions: The “white line”—the mucosal boundary between nasopharynx and oropharynx—has a correlation with laryngopharyngeal reflux.