Montreal Cognitive Assessment (MoCA) test is an auxiliary medical screening method for Alzheimer's disease (AD). During the traditional process, a testee is required to conduct several test items on the paper questionnaire following the guidance of a medical staff. It is inefficient and dependents largely on the doctor's subjective judgment and experience level. Therefore, we propose an Interactive and Intelligent AD Auxiliary Screening (IAS) system consisting of speech-based Interactive Unit Testing Module (IUTM) and truth-based Intelligent Analysis Module (IAM), both of which are developed by deep learning techniques. Following the guidance of voice commands, the testee could achieve the MoCA test independently in IUTM just by a mobile device, and then the testing data is analyzed accurately and objectively by IAM. Moreover, the electronic system is beneficial to collect and analyze clinical data for further research compared to the traditional method. And the system is deployed in the Department of Neurology, Sichuan Provincial People's Hospital in June 2021 and has been used in the clinical screening of Alzheimer's disease.