Patients with preclinical left ventricular (LV) diastolic dysfunction (DD) are prone to develop heart failure with preserved ejection fraction. Although left atrial (LA) enlargement and deterioration of LA function in apparent DD and heart failure with preserved ejection fraction have been previously described, data regarding phasic LA strain (LAS) in preclinical DD are scarce. In a cross-sectional trial, echocardiographic parameters of DD, LA volume index, and global LA reservoir, conduit, and pump function were prospectively analyzed in 473 women from the general population in Berlin, Germany (BErlin Female RIsk evaluation (BEFRI) study), using standard and two-dimensional speckle-tracking echocardiography. One hundred thirty-one women (29.7%) showed early-stage DD (impaired relaxation DD1) and 22 (5.0%) showed an echocardiographically more advanced stage of DD (pseudonormal filling DD2). Compared with women with normal diastolic function (DD0), those with DD1 displayed lower LA reservoir and conduit function (DD0, 43.2 ± 8.5% and 27.2 ± 8.0%; DD1, 33.3 ± 8.0% and 16.1 ± 7.1%; P < .001) but significantly higher LA pump function (DD0, 17.6 ± 5.4%; DD1, 18.9 ± 5.5%; P < .05). In patients with DD2, all three phases of LAS were markedly impaired compared with those with DD0 (reservoir, conduit, and pump function, 29.0 ± 6.3%, 15.1 ± 5.4% P < .001, and 14.9 ± 4.1% P < .05, respectively). LA reservoir and conduit function was significantly associated with DD; in receiver operating characteristic curve analysis, these parameters showed higher diagnostic accuracy in detecting early DD compared with LA volume index. In multivariate analysis, LA reservoir strain remained significantly associated with DD. All three components of LAS showed specific alterations in different stages of DD. LA reservoir and conduit function was markedly reduced before symptoms, LA enlargement, and elevations of noninvasively estimated LV filling pressures occurred. Analysis of LA function featured higher discriminative strength in diagnosing early-stage DD compared with the well-established parameter LA volume index. Assessment of LAS allows diagnosis of impaired LA function and DD in a subclinical stage and might enable timely preventive and therapeutic interventions.