The accurate diagnosis of latent left ventricular outflow tract obstruction (LVOTO) in non-hypertrophic cardiomyopathy (NHCM) is crucial for treatment selection. This study evaluates the diagnostic value of stress echocardiography (SE) in detecting LVOTO in NHCM patients. We retrospectively analysed SE data from33NHCMpatients with latent LVOTO and 35 NHCM patients without LVOTO, collected between January 2021 and July 2025. Key echocardiographic findings showed significantly greater posterior mitral leaflet length (1.97 ± 0.21 cm vs. 1.35 ± 0.43 cm), anterior mitral leaflet length (2.68 ± 0.70 cm vs. 2.16 ± 0.60 cm), and mitral valve coaptation length (1.04 ± 0.17 cm vs. 0.51 ± 0.22 cm) in the latent LVOTO group. The peak systolic flow velocity (4.75 ± 1.35 m/s vs. 1.92 ± 0.75 m/s) and pressure gradient (91.08 ± 10.36 mmHg vs. 16.36 ± 5.68 mmHg) were significantly higher in the latent LVOTO group. SE is an effective tool for diagnosing latent LVOTO in NHCM, enhancing clinical decision-making.