Objective To explore the intervention effect of a square stepping exercise program on elderly people with mild cognitive impairment(MCI) living in an elderly care institution,aiming to provide references for clinical practice. Methods The square stepping exercise program was developed through literature review,expert consultation and a pilot study. In this randomized controlled trial,70 elderly people with MCI from a nursing institution in Hangzhou from July to October 2025 were selected as research subjects through convenience sampling. They were randomly divided into an experimental group and a control group(35 cases in each group). The experimental group received the square stepping exercise program for 12 weeks in addition to routine care in the elderly care institution,while the control group received routine care only. Cognitive function,balance function,mobility,and quality of life were compared between the 2 groups before and after the intervention. Results Eventually,33 cases in the experimental group and 34 cases in the control group completed the study. After the 12-week intervention,the scores in the experimental group had significant statistical differences in Montreal Cognitive Assessment,visuospatial and executive function,attention,delayed recall,Berg Balance Scale,Timed Up and Go Test and physical and mental health of 12-item Short-Form Health Survey compared with those in the control group(P<0.05). No exercise-related adverse events occurred in the experimental group. Conclusion The square stepping exercise program is safe and feasible,and it can effectively delay the progression of cognitive decline in elderly people with MCI in nursing institutions,and improve their balance function,mobility and quality of life.