The purpose of this study is to determine the correlation between descending movement of the diaphragm during breathing and respiratory function, respiratory muscle strength, and activities of daily living (ADL) in subacute stroke patients. The subjects of this study consisted of 29 subacute stroke patients hospitalized in the hospital, including 17 adult men and 12 adult women. The diaphragm was measured during quiet breathing and deep breathing in a supine position, and ultrasound M-mode was used to measure the movement of the diaphragm during breathing. To evaluate the respiratory function, forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) were measured using spirometer. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were measured to evaluate the respiratory strength using Micro RPM. In clinical trial, functional independent measure (FIM) and fatigue severity scale (FSS) were measured. In this study, FVC showed a significant positive correlation (p<.01) between PDDB (r=.44) and NDDB (r=.57). FEV1 showed a significant positive correlation (p<.05) between PDQB (r=.45), NDQB (r=.42), and NDDB (r=.53). MIP showed a significant positive correlation (p<.05) between PDQB (r=.38), PDDB (r=.43), NDQB (r=.38), and NDDB (r=.68). MEP showed a significant positive correlation (p<.05) between PDDB (r=.38), NDQB (r=.44), and NDDB (r=.54). FIM showed a significant positive correlation (p<.05) with PDDB (r=.45). As the descending movement of diaphragm is positively correlated with respiratory function, respiratory muscle strength, and ADL, diaphragmatic breathing training which induces the descending movement of diaphragm in stroke patients is considered to be important.