Impaired visual feature binding has recently been proposed as a sensitive and specific cognitive marker for early stages of Alzheimer Disease (AD), based on data from AD patients and from asymptomatic carriers of AD mutations. In order to examine feature binding also in patients at risk of AD, where early detection of AD is particularly important, we studied patients with subjective cognitive decline (SCD) and patients with amnestic MCI (aMCI). Memory clinic patients with SCD (cognitive performance within 1 SD of the normative mean in standard neuropsychological testing, n=20, mean age 68 years), patients with aMCI (>1.5 SD deficit in delayed verbal recall, n=17, mean age 72 years) and cognitively normal elderly (n=13, mean age 66 years) were assessed with the feature binding task (Parra et a. 2010, Brain) and with the CERAD neuropsychological battery (CERAD). The proportion of correctly detected feature binding (shape-color) changes in two successive visual displays, each containing three geometric objects, was compared between groups. Both at-risk groups, SCD and aMCI, were impaired in detecting feature binding changes, and aMCI were more impaired than SCD. Adjusting for age, sex, and education, performance of SCD patients (p < 0.001) and of aMCI patients (p < 0.001) was lower than in Controls. SCD could be discriminated from Controls with good diagnostic accuracy with the feature-binding task (AUC = 0.812), but not with delayed verbal free recall (AUC = 0.486). Feature binding proved to be a sensitive measure for detecting cognitive deficits in subjects in putatively prodromal stages of AD. The data also provide further evidence for SCD being associated with subtle cognitive impairments, which can be uncovered only with novel neuropsychological tasks.