Objective To investigate the incidence of frailty in elderly patients with stable coronary artery disease (CAD), analyze the related clinical indicators, and determine the effect of frailty on short-term outcomes of the patients. Methods Consecutive 153 outpatients aged ≥65 years in the Departments of Geriatrics and Cardiology from December 1, 2014 to April 30, 2015 were recruited in this study. Comprehensive geriatric assessment and clinical frailty scale (CFS) were employed to survey their conditions and frailty. The CAD-specific comorbidity index was used to quantify the effects of the comorbid conditions. Unscheduled return visits (URV) and all-cause mortality were observed during follow-up. Results For the 153 patients, 69 (45.10%) were assigned into the frail group, and 84 (54.90%) into the non-frail group according to the results of CFS. The former group also included 33 cases of moderately or severely frailty, accounting for 21.57% (33/153). Grip strength and gait speed were significantly lower, while the serum levels of IL-6 and high-sensitivity C-reactive protein (hs-CRP) were obviously higher in the frail group than in the non-frail group (P<0.05). For frail diagnosis, the cutoff value for hand grip strength was 29.85 kg for men and 19.50 kg for women, and that for usual gait speed was 0.879 m/s for men and 0.870 m/s for women. Cox regression analysis showed that CFS scale was the independent predictive factor for URV risk for stable CAD patients (HR=3.312, 95%CI:1.439-7.621, P=0.005). Conclusion Elderly patients with stable CAD have higher incidence of frailty, and special attention should be paid to those with moderate-severe frailty. Gait speed and grip strength can be used as indicators for frailty assessment. CFS score is an independent predictor factor for URV risk of the elderly with stable CAD.