In this study, we conducted a 2-sample Mendelian randomization (MR) analysis to explore the relationship between gastroesophageal reflux disease (GERD) and 16 common otolaryngological diseases. Single-nucleotide polymorphisms that are strongly associated with GERD were used as instrumental variables. The primary estimation of the causal effect utilized the inverse variance weighting method, supplemented by MR Egger, weighted median, simple mode, and weighted mode as alternative methods for estimating the causal effect. Then, sensitivity analyses, including heterogeneity, pleiotropy, and leave-one-out analyses, were performed to verify the robustness of the results. The analysis of MR showed that genetically predicted GERD was associated with an increased risk of acute upper respiratory infection (odds ratios [OR] = 1.1418, 95% confidence intervals [CI] = 1.0664-1.2225, P = 1.00 × 10-4), chronic pharyngitis (OR = 1.483, 95% CI = 1.1495-1.9132, P = 2.40 × 10-3), vocal cord dysfunction (OR = 2.2963, 95% CI = 1.4174-3.7201, P = 7.00 × 10-4), sleep apnea (OR = 1.0022, 95% CI = 1.0009-1.0035, P = 8.00 × 10-4), acute sinusitis (OR = 1.3247, 95% CI = 1.1774-1.4905, P = 2.94 × 10-6), chronic sinusitis (OR = 1.3649, 95% CI = 1.1854-1.5715, P = 1.52 × 10-6), chronic suppurative otitis media (OR = 2.085, 95% CI = 1.3292-3.2704, P = 1.40 × 10-3). Further sensitivity analyses showed no evidence of pleiotropy. The results of this study indicate that GERD may contribute to the development of some otolaryngological diseases. Further research and mechanistic investigations are warranted to elucidate the underlying connections and potential therapeutic implications.