Background and Objectives: Neck and shoulder injuries are common in Brazilian ju-jitsu (BJJ) athletes, and scapular dyskinesis (SD) is associated with these injuries. This study aimed to investigate the prevalence of SD in BJJ athletes, their neck and shoulder function and strength, and the BJJ training period. Materials and Methods: Forty-eight BJJ athletes participated in the study. Years of experience with BJJ, belt, shoulder internal and external rotation strength, neck strength, neck disability index (NDI), and SD were measured. Results: Approximately 31 BJJ athletes (64.6%) showed SD, and the nondominant arm showed a more obvious SD (n = 22, 45.8%) than the dominant arm (n = 18, 37.5%). Those with over five years of BJJ training experience showed a significantly higher rate of SD (p = 0.006) than those with less than five years of experience. Shoulder isometric internal rotation strength was significantly weaker in the obvious SD group than in the normal SD group (p = 0.014). Neck isometric strength and NDI did not differ significantly between individuals with or without SD. Conclusions: SD was common among BJJ athletes, and more experienced BJJ athletes exhibited higher rates of SD. Shoulder rotational strength was weaker with SD. Further studies are necessary on the neck and shoulders of BJJ athletes with SD.