Carbon monoxide (CO) poisoning is considered one of the most crucial health concerns. Few studies have investigated the correlation between CO poisoning and the risk of developing cardiovascular diseases (CVDs). Therefore, we conducted a population-based, longitudinal cohort study in Taiwan to determine whether patients with CO poisoning are associated with higher risk of developing subsequent CVDs, including arrhythmia, coronary artery disease (CAD) and congestive heart failure (CHF). This retrospective study used the National Health Insurance Research Database. The study cohort comprised all patients aged ≥20 years with a diagnosis of CO poisoning and hospitalized during 2000 to 2011 (N = 8381), and the comparison cohort comprised randomly selected non-CO-poisoned patients (N = 33,524) frequency-matched with the study cohort by age, sex, and the year of index date. Each patient was individually tracked to identify those who develop CVD events during the follow-up period. Cox proportional hazards regression model was performed to calculate the hazard ratios of CVDs after adjusting for possible confounders. The overall incidences of arrhythmia, CAD, and CHF were higher in the patients with CO poisoning than in the controls (2.57 vs 1.25/1000 person-years, 3.28 vs 2.25/1000 person-years, and 1.32 vs 1.05/1000 person-years, respectively). After adjusting for age, sex, and comorbidities, the patients with CO poisoning were associated with a 1.83-fold higher risk of arrhythmia compared with the comparison cohort, and nonsignificantly associated with risk of CAD and CHF. CO-poisoned patients with coexisting comorbidity or in high severity were associated with significantly and substantially increased risk of all 3 CVDs. CO poisoning is associated with increased risk of subsequent development of arrhythmia. Future studies are required to explore the long-term effects of CO poisoning on the cardiovascular system.