Objectives: The aim of this study was to define the phenotypic spectrum of apical hypertrophic cardiomyopathy (ApHCM) and clinical characteristics pertaining to identified subtypes. Methods: In 182 consecutive ApHCM patients (58.9 ± 11.2 years; 142 men) with left ventricular ejection fraction ≧50%, we measured end-diastolic wall thickness of all 16 left ventricular segments to determine patterns of hypertrophy. Echo-Doppler parameters, electrocardiography patterns, and clinical findings were analyzed. Results: ApHCM was classified into three types as pure focal (n = 81), pure diffuse (n = 70) and mixed type (n = 31) according to patterns of hypertrophy. Incidence of atrial fibrillation (5% for pure focal vs. 11% for pure diffuse vs. 23% for mixed type, p < 0.05) and left atrial volume index (30.9 ± 11.8, 35.7 ± 14.8, and 41.3 ± 15.9 ml/m<sup>2</sup>, respectively, p < 0.001) were significantly different among subtypes. Peak systolic (6.6 ± 1.0 vs. 6.3 ± 1.2 vs. 5.9 ± 1.1 cm/s, respectively, p < 0.05), diastolic (5.1 ± 1.8 vs. 5.0 ± 1.2 vs. 4.1 ± 1.3 cm/s, respectively, p < 0.05) mitral annular velocity, E/E′ (13.3 ± 4.2 vs. 13.7 ± 5.4 vs. 16.1 ± 6.1, respectively, p < 0.05) were also significantly different. Conclusions: ApHCM contains three morphologically distinct phenotypes and detailed subtyping is important in the prediction of development of atrial fibrillation, left atrial volume index and left ventricular longitudinal function.