To explore the effect of social support on the self-efficacy and quality of life of elderly patients with mild cognitive impairment (MCI). Methods: Convenience sampling was used to select 206 MCI patients in our hospital. A survey and analysis were conducted on patients and their family using the general demographic data questionnaire, perception of social support scale (PSSS), general self-efficacy scale (GSES), and Chinese translation of the Alzheimer’s disease quality of life scale (QOL-AD). Results: The 206 MCI patients had a QOL-AD total score of (32.05±2.31), GSES score of (33.45±3.57), and PSSS score of (53.14±4.35), all of which were considered low-moderate levels. Patients with a different age, education level, location of residence, condition of residence, family income, mode of medical expense, and quality of interpersonal relationships showed a significant difference in QOL-AD score (P<0.05). All item scores on the QOL-AD were positively correlated with the social support score of the PSSS (P<0.05). The physical health, energy, mood, living conditions, memory, relationship with family members, marital status, and overall feelings about oneself item scores on the QOL-AD were significantly positively correlated with the GSES total score (P<0.05). Conclusion: Clinical medical staff should recognize the self-efficacy of elderly patients with MCI, promote the utilization of social support, and formulate scientifically feasible and high-quality self-management projects and programs, so as to improve the quality of life and delay the progression of Alzheimer’s disease.