Patients with cardiovascular disease and cognitive impairment show reduced adherence to treatment. No study has examined whether cognitive impairment may also predict reduced benefit from cardiac rehabilitation (CR). It appears that cognitively impaired patients may exhibit poorer adherence to CR and limited gains in cardiovascular fitness and/or quality of life (QOL). Forty‐four older adults who enrolled in a CR program and completed measures at enrollment and discharge were included. Cognitive functioning was assessed using the Trail Making Test B. Estimated metabolic equivalents (METs) were derived from a treadmill stress test to provide a measure of cardiovascular fitness. QOL was measured with the Short Form‐36 (SF‐36) physical and mental component scales (PCS and MCS, respectively). Repeated measures analysis of variance showed improvements in METs [METs; F(1,36)=77.6, P<.001] and physical [SF‐36 PCS; F(1,36)=14.14, P=.001)] and mental QOL [SF‐36 MCS; F(1,36)=11.55, P=.002)]. Partial correlations indicated that poorer Trail Making Test B performance was associated with lower METs at discharge (r=−0.30, P<.05), but not PCS or MCS. Mini‐Mental State Examination scores were not related to outcome variables. Current findings suggest that patients with poorer executive functioning derive reduced benefit from CR. CR programs may consider screening patients at baseline for low cognitive functioning to help identify those patients at greatest risk for poor outcome. Prev Cardiol. 2010;13:100–103.©2009 Wiley Periodicals, Inc.