Objective: To explore the electrocardiogram characteristics and diagnostic value of patients with arrhythmia-type cardiomyopathy. Methods: A total of 92 patients with arrhythmia-type cardiomyopathy admitted to our hospital from October 2023 to October 2024 were selected and divided into the typical group (47 cases) and the atypical group (45 cases) based on the characteristics of electrocardiogram manifestations. The electrocardiogram of patients in the typical group showed obvious characteristic changes, while the electrocardiogram of patients in the atypical group was atypical. The electrocardiogram parameters (QRS duration, QT interval, T-wave changes, etc.), cardiac function indicators, occurrence of arrhythmia and follow-up prognosis of the two groups of patients were compared. Results: The incidences of prolonged QRS wave duration, prolonged QT interval and inverted T wave in the typical group were all higher than those in the atypical group, and the difference was statistically significant (t=3.842, P < 0.05). The incidence of ventricular rate disorders in the typical group was significantly higher than that in the atypical group, and the difference was statistically significant (χ2=6.372, P < 0.05). The left ventricular ejection fraction (LVEF) of patients in the typical group was significantly lower than that in the atypical group, and the difference was statistically significant (t=5.436, P < 0.05). After a 6-month follow-up, the incidence of adverse cardiac events in the typical group was higher than that in the atypical group, and the difference was statistically significant (χ2=3.775, P < 0.05). Conclusion: The electrocardiogram (ECG) manifestations of patients with arrhythmic cardiomyopathy have certain characteristics. Typical ECG changes are closely related to the cardiac function status of patients, the incidence of arrhythmia and prognosis, which is of great value for the early diagnosis and risk assessment of this disease.