Objective: To explore the relationship between color Doppler echocardiography indexes and electrocardiogram heart rate variability (HRV) parameters and grading and prognosis of chronic pulmonary heart disease (CPHD). Methods: A total of 90 patients with CPHD admitted to the hospital from June 2022 to October 2024 were selected and divided into grade II group (n=28), grade III group (n=35) and grade IV group (n=27) according to New York Heart Association (NYHA) cardiac function grading method. They were followed up for 6 months and classified into death group (n=10) and survival group (n=80) according to the prognosis status. The color Doppler echocardiography indexes and electrocardiogram HRV parameters were compared among CPHD patients with different NYHA cardiac function grades and different prognoses. Spearman correlation test was used to analyze the relationship between color Doppler echocardiography indexes and electrocardiogram HRV parameters and NYHA cardiac function grading and prognosis of CPHD patients. Results: LVESD, LVEDD, LA and LF/HF in grade IV group were higher than those in grade II group and grade III group (P<0.05) while LVEF, E/A, SDANN, SDNN, RMSSD and PNN50 were lower than those in grade II group and grade III group (P<0.05), LVESD, LVEDD, LA and LF/HF in grade III group were higher (P<0.05) while LVEF, E/A, SDANN, SDNN, RMSSD and PNN50 were lower than those in grade II group (P<0.05). LVESD, LVEDD, LA and LF/HF in death group were higher than those in survival group (P<0.05) while LVEF, E/A, SDANN, SDNN, RMSSD and PNN50 were lower (P<0.05). Spearman correlation analysis showed that LVESD, LVEDD, LA and LF/HF were positively correlated with NYHA cardiac function grading and prognosis (P<0.05), while LVEF, E/A, SDANN, SDNN, RMSSD and PNN50 were negatively correlated with NYHA cardiac function grading and prognosis (P<0.05). Conclusion: Cardiac color Doppler echocardiography indexes and electrocardiogram HRV parameters are closely related to cardiac function grading and prognosis of CPHD patients, and can be used as auxiliary indexes to evaluate cardiac function grading and prognosis of CPHD patients.