Acute aerobic exercise may increase cognitive processing speed among tasks demanding a substantial degree of executive function. Few studies have investigated executive function after acute exercise in older adults across various exercise intensities. Healthy females 60-75 years of age (n = 11) who were not on medications completed 20-min exercise sessions at a moderate (50%VO₂max) exercise intensity and a vigorous (75%VO₂max) exercise intensity. Modified flanker tasks (reaction times) and d2 tests of sustained and selective attention (components of executive function) were completed before, immediately after, and 30-min post-exercise. Results indicated that older adult females had improved scores on the modified flanker task reaction times (RT_T, RT_I, RT_C) and d2 tests immediately after both moderate and vigorous intensity aerobic exercise. Some of these effects were maintained 30 min post-exercise. These findings suggest that an acute bout of exercise, regardless of intensity, can improve performance on tests of executive function in older women.