OBJECTIVE: To associate motivation with diet quality in older people (OP) who practice running. METHODS: Cross-sectional observational analytical study, which was applied to a probabilistic sample of OP who practice running. Each participant was applied a survey including sociodemographic variables and experiences concerning the practice of Running, diet quality questionnaire for OP (ECAAM, for its acronym in Spanish) and the Motivation of Marathoners Scales-34 (MOMS-34) were used. RESULTS: The total number of participants was 68, who were mostly men (69.1%), the predominant age was 60–69 years (69.1%). Women showed a higher proportion in diet quality when compared to men (71.4% vs 36.2%). The association between motivation subscales and food groups showed that the Weight Concern subscale was associated with junk food (Δ=1.55 (95% CI: 0.58; 2.52). The Personal goal achievement-Competition subscale was associated with meat (Δ=1.81 (95% CI: 0.62; 3.00). Recognition was associated with meat (Δ=1.12 (95% CI: 0.22; 2.03), and Health Orientation with alcohol (Δ=0.76 (95% CI: 0.02; 1.50). CONCLUSIONS: Motivation is positively associated with diet in OP who practice running, especially for the motivation subscales Weight Concern, Personal goal achievement-Competition, Recognition and Health orientation.