Background: Multisociety guidelines recommend a goal systolic blood pressure (BP) <130 mm Hg and a hemoglobin A1c (HbA1c) <8% in patients with heart failure (HF), regardless of ejection fraction. Few studies have described BP and glycemic control in ambulatory patients with HF and racial and ethnic disparities in this subset of the population. Methods: We evaluated prevalence of uncontrolled BP and HbA1c in non-Hispanic Black, non-Hispanic White, and Mexican American adults aged ≥20 years with self-reported HF (National Health and Nutrition Examination Surveys: 2001–2018). Prevalence ratios (95% CI) for uncontrolled BP and HbA1c were calculated by race and ethnicity and adjusted for sex, age, treatment, and socioeconomic status. In secondary analyses, we examined trends in the prevalence of uncontrolled BP and HbA1c. Results: Uncontrolled BP was present in 48% (95% CI, 49%–56%) of adults with HF (representing 2.3 million people). Non-Hispanic Black participants had a higher prevalence of uncontrolled BP compared with non-Hispanic White participants (53% [48%–58%] compared with 47% [43%–51%], P <0.05). In adjusted models, non-Hispanic Black participants were 1.19 (1.02–1.39) times more likely to have uncontrolled BP than non-Hispanic White participants. Overall, uncontrolled HbA1c was found in 8% (6%, 10%) with no differences by race and ethnicity. Prevalence of uncontrolled BP improved over time but uncontrolled risk factors remained high—2017 to 2018: 41% (36%, 47%) and 7% (5%, 12%) had uncontrolled BP and HbA1c, respectively. Conclusions: We document an unacceptably high prevalence of uncontrolled BP and HbA1c in a nationally representative, ambulatory HF sample with significant differences in BP control by race and ethnicity.