The COVID-19 pandemic has significantly impacted individuals' mental health, resulting in a higher incidence of depression, anxiety, and changes in eating behaviors. The objective of this study is to examine the inter-relationships among obesity-related eating behavior, depression, and anxiety in adults during the COVID-19 pandemic, utilizing a network analysis method. We conducted a cross-sectional survey among a representative sample of 9091 adults between July 10 and September 15, 2021. Participants completed self-report measures to assess obesity-related eating behavior and symptoms of depression and anxiety. Network analysis was employed to investigate the inter-relationships among these variables. The network analysis revealed that item 2 (i.e., Do not feel satisfied unless I eat until full) exhibited the highest node strength within the network, followed by item 5 (i.e., Like oily foods). In addition, positive correlations were found between the severity of depression and anxiety and most of the obesity-related eating behavior items. These findings offer valuable insights into the interplay between obesity-related eating behavior, depression, and anxiety during the COVID-19 pandemic, underscoring the significance of considering these factors in comprehending and addressing mental health and well-being in adults. Further research is warranted to explore potential interventions and treatment approaches that specifically target the identified relationships.