In recent years, with the development of ultrasound technology, pulmonary ultrasound is more and more used in the evaluation of patients with heart failure. B-lines are defined as reverberation artifacts starting from the pleural line and extending to the bottom of the screen without disappearing, and moving synchronously with pleural sliding, which are proportional to extravascular lung water in congestive heart failure (CHF). B-lines have the characteristics of no attenuation and synchronous movement with pleural sliding. Pulmonary ultrasound mainly record the numbers and widths of B-lines in the areas when assessing the severity of CHF, which have the characteristics of effectivity, non-invasiveness, instantaneousness, and good repeatability. Currently, there are 4-, 8-, 12-, and 28-subdivision methods for the evaluation of CHF in the pulmonary ultrasound subdivision method. The more subdivisions are, the longer the operation time will be, and the sensitivity and specificity will be different. How to choose a subdivision method is still controversial in clinical practice. Lung ultrasound could be used alone or combined with brain natriuretic peptide, echocardiography, chest X-ray, chest CT scan, etc. in the early diagnosis, assessment of disease severity, evaluation of efficacy, and assessment of prognosis of CHF, with different advantages and disadvantages. This article reviews the application and progress of pulmonary ultrasound in CHF.