Background: To explore the dynamic network structure and centrality of depressive and anxiety symptoms before the peak of COVID-19 and during the COVID-19 outbreak in the post-COVID-19 era. Methods: A web-based survey was conducted in two stages: the pre-peak stage in the post-COVID-19 era and the outbreak stage in the post-COVID-19 era. The Patient Health Questionnaire-9 (PHQ-9) and General Anxiety Disorder-7 (GAD-7) scales were used. Network models were created to explore the relationship between psychopathology symptoms both within and across anxiety and depression. Symptom network analysis was conducted to evaluate network and bridge centrality, and the network properties were compared between the pre-peak and the outbreak stage. Results: A total of 1849 participants in the pre-peak stage and 1363 participants in the COVID-19 outbreak stage in the post-COVID-19 era were recruited. D4 “Fatigue” and A4 “Trouble relaxing” had the highest expected influence during the outbreak stage. D2 “Depressed or sad mood”, D5 “Appetite changes”, and D6 “Feeling of worthlessness” played an important role in the network during the peak of the postpandemic era. Conclusions: This study provides novel insights into the changes in central features during different COVID-19 stages that could activate the connection between anxiety and depression. Implications for interventions and clinical preventions are discussed.