Alzheimer's disease (AD) which is the most common cause of dementia, has two subtypes: early-onset and late-onset AD. Early-onset AD affects people younger than age 65 and memory dysfunction, cognitive impairment, executive dysfunction and language problems are relatively more common on patients with early-onset AD. Based on the language disturbances, the aim of this study is to examine basic sentences of patients with early-onset AD by using four different language tests and to compare all the results with a control group. Considering the power analyses, 23 patients with early-onset AD from Dokuz Eylul University, Faculty of Medicine, Department of Neurology and an age/education-matched control group are included in this study. The data were analyzed using t test and Mann-Whitney U test. It was found that patients with early-onset AD used more basic sentences in Random Speech test compared to the control group. The other finding was about the nominal and the verbal sentences. It was revealed that there was a statistically significant difference between the patients with earlyonset AD and the control group in terms of nominal sentences in the Picnic Picture description test, Cookie Theft Picture description test and the Story Picture Sequencing test. In terms of verbal sentences, it was found that there was a statistically significant difference between the patients with early-onset Alzheimer’s disease and the control group in all language tests. In conclusion, the syntactic ability is preserved in AD. However, working memory problems can make the syntactic processing worse. Due to this process, patients with early-onset AD tend to use basic sentence structures more frequently. Keywords: alzheimer, early-onset alzheimer’s disease, basic sentences, nominal sentences, verbal sentences