Nutrition plays a crucial role in the pathophysiology and management of peripheral arterial disease (PAD) and periodontal disease (PD). As PD can have profound effects on an individual’s functional ability to eat and can affect nutrient intake, we aimed to evaluate the role of PD severity on dietary intake (DI) and quality in PAD patients and compare it to current dietary recommendations for cardiovascular disease (CVD). PD stages of 421 consecutive PAD patients were determined according to a standardised basic periodontal examination (PSR) (“healthy”, “gingivitis”, “moderate periodontitis” and “severe periodontitis”). Dietary intake (24-h recall), dietary quality (food frequency index [FFI]), and anthropometrical data were assessed. Nutritional intake was stratified according to the severity of PD. No significant differences in DI of macronutrients, nutrients relevant for CVD and FFI were seen between the PD stages. Only median alcohol intake was significantly different between gingivitis and severe periodontitis (p = 0.001), and positively correlated with PD severity (p = 0.001; r = 0.159). PD severity and the patient’s number of teeth showed no correlation with investigated nutritional parameters and FFI. Few subjects met the recommended daily intakes for fibre (5%), saturated fatty acids (10%), sodium (40%) and sugar (26%). Macronutrient intake differed from reference values. In our sample of patients with PAD and concomitant PD, we found no differences in DI of macronutrients, nutrients relevant for CVD, and diet quality depending on PD severity. The patients’ nutrition was, however, poor, deviating seriously from dietary guidelines and recommendations.