Through reviewing literatures, we analyzed the infection characteristics in senile patients and features of antibacterial treatment optimization in them. On the basis of rational selection of antibiotics, we focused on and had a full understanding of the pathogenic bacteria, susceptibility to infections, clinical symptoms, condition changes, complications, clinical course, and efficacy and adverse reactions of antibiotic drugs in the elderly. In this article, based on the principles of clinical use of antibiotics and the characteristics of pharmacokinetics/pharmacodynamics (PK/PD) in these patients, we summarized the research progress in categories, dosage, treatment course and interphase, and combined use of antimicrobial drugs for the elderly with infective diseases. We aimed to fully grasp the infection characteristics and antibacterial treatment optimization so as to provide a theoretical basis for safer and more rational selection and use of antimicrobial agents for them.