There are currently more than 3.3 million prostate cancer (PC) survivors in the United States. Conformance with national dietary guidelines and a good diet quality may lower the risk for Gleason grade progression in PC patients. Assessing the nutritional status of PC survivors is thus of paramount importance from a public health nutrition perspective. We used 24-h dietary recall data from the National Health and Nutrition Examination Surveys (NHANES) to systematically estimate nutrient intakes in n = 360 PC survivors (which may be extrapolated to represent n = 1,841,030 PC survivors) aged 70.69 years on average, and contrasted the results to the daily nutritional goals (DNG) in the 2020–2025 Dietary Guidelines for Americans (DGA). Diet quality in PC survivors was found to be generally poor, and the DNG as specified in the DGA were not met for many micronutrients, including calcium, magnesium and potassium. PC survivors had an insufficient intake of many vitamins (including vitamins A, C, D and E), and did not meet the intake recommendations for dietary fiber. Racial disparities in PC were reflected in the lower overall DQ in Non-Hispanic Black participants. Our results reiterate the need for nutritional assessment and counseling to improve DQ in PC patients.