Background: Adults with gastroesophageal reflux disease (GERD) are susceptible to mental disorders that might significantly affect their health-related quality of life (HRQoL). Therefore, the purpose of this study was to evaluate how HRQoL in individuals with GERD is related to coexisting anxiety and depression. Methods: A cross sectional study was conducted among 3068 adult patients 22 years of age and older with GERD diagnoses have been identified using the data from the Medical Expenditure Panel Survey from 2017 to 2020 for United States adults. Data are gathered by MEPS using an overlapping panel design over a period of two and a half years. HRQoL was established using the Physical and Mental Component Summary (PCS & MCS) values from the SF-12. Multivariate forward linear regression analysis was used to assess the relationship between anxiety, depression, and HRQoL in people with GERD after accounting for various factors. Results: Of the 3068 people with GERD who had been identified, 56.4% were women, 59.4% were in their 50s or 60s and 64.8% were employed. Thirteen per cent of people with GERD had depression, thirteen per cent had anxiety, and ten per cent had both. Adults with concurrent anxiety and depression had the lowest mean PCS and MCS scores compared to those with GERD. After adjusting for all independent factors, GERD patients with anxiety (MCS = −10.819, p-value < 0.0001), depression (MCS = −6.395, p-value < 0.0001), and both (MCS= −42.869, p-value < 0.0001) had substantially worse HRQoL than those without these comorbidities. Notably, better HRQoL scores were positively associated with marital status, employment, perceived overall health, and physical activity. Conclusions: The results from this nationally representative sample shed insight into the relationships between low HRQoL and anxiety and depression among individuals with GERD. It also demonstrated the detrimental impacts of co-occurring chronic illnesses, low socioeconomic status, and the positive benefits of employment and exercise on HRQoL. This study emphasizes the clinical, policy, and public health implications for better healthcare, allocation of resources, and promotion of lifestyle modifications to improve the HRQoL in patients with GERD.