Objective To investigate the clinical efficacy of BiPAP in the treatment of heart failure with reduced ejection fraction (HFrEF) by pulse induce contour cardiac output (PICCO) monitoring technology. Methods A total of 358 HFrEF patients admitted to The People's Hospital of Xinjiang Uygur Autonomous Region from January 2017 to December 2020 were included. There were 208 patients with noninvasive ventilators assisted ventilation (NIPPV), amongwhom 146 patients had PICCO monitoring indications and signed informed consent. The parameters were divided into BiPAP group (n=74) and Mask oxygen group (n=72) by random digitalization. Pressume PICCO coefficient and percentage of mechanical ventilation were compared at 4 h after intervention. Referring to EVLWI, we presume that 39 cases were found with COEFFICIENT (PICCO+BiPAP) in BiPAP intervention group, and 30 cases were found with mask oxygen inhalation (PICCO+ mask oxygen inhalation). PICCO data were measured at 0 (baseline), 4, 8, 12 and 24 h, respectively. The changes of BNP, blood gas, CI, EVLWI and ITBVI in each group were statistically analyzed. The incidence of cardiogenic death, malignant arrhythmia, cardiogenic shock and the conversion rate of non-invasive intubation were analyzed.Results Compared with mask oxygen intake group, BiPAP group had a lower probability of mechanical ventilation, oxygen partial pressure recovered faster at 4 h, and EVLWI decreased (allP＜0.05). Taking EVLWI≥10 as the limit, we presume that BiPAP assisted EVLWI patients had more obvious clinical effect, and presume that BiPAPassisted EVLWI patients gradually decreased, cardiac index increased, and intrathoracic blood volume index decreased (P＜0.01). We presume that there was no statistical difference between THE above-mentioned indexes in EVLWI＜10 groups (P＞0.05). In HF patients with EVLWI≥10, compared with mask oxygen intake, BiPAP therapy was more effective, and mechanical ventilation was lower and cardiac lipid number increased (P＜0.011).Conclusion BiPAP mode is beneficial for patients with EVLWI≥10 to assist ventilation, reduce BNP, increase CI, reduce invasive mechanical ventilation and improve the success rate of rescue.