This study examined the effects of subjective age and attitudes about aging on frequency of sex and interest in sexual activity among middle-aged and older adults. Data were drawn from two waves of the Midlife in the United States (MIDUS) study (n = 1,170 adults, mean age Time 1 = 53.70 years, SD = 9.08). Regression analyses were used to investigate the effects of subjective age and attitudes about aging on three measures of sexuality: frequency of sex, perceived quality of sexual activity, and interest in sexual activity, over 10 years. The older participants felt and the less positive their views of aging, the less they rated sexual activity as enjoyable over time. Feeling older (though not attitudes about aging) also predicted less interest in sex. Subjective age and beliefs about aging did not have an impact on frequency of sex. Although frequency of sex was not predicted by subjective aging and aging attitudes, the results suggested that subjective age and stereotypic views on aging may shape the experience of sex in later life.