Background: Maintaining good physical functioning in old age is of utmost importance for healthy and active aging. We examined physical function and associated factors in the oldest-old men. Subjects and methods: The participants of this cross sectional analysis of a longitudinal study were the oldest old men(n=394, mean age 88 years, range 82-97 years) from the Helsinki Business Men cohort who responded to a postal health and nutrition survey in 2016. Physical function was defined using the respective subscale (Physical Function, PF) in the RAND-36 health-related quality of life (HRQoL) instrument. Resilience was measured with validated Finnish version of Resilience scale. Diet quality was assessed using Mediterranean diet adherence score (MeDi) and Diet quality index (DQI) which is designed to show adherence to Finnish dietary recommendations. Food and dietary intakes were retrieved using 3-day food records (obtained from a subgroup of the respondents). The participants were divided into quartiles corresponding to their PF scores and health and nutrition indicators were calculated into these PF quartiles. Furthermore, a linear regression model was used to determine factors associated with PF. Results: PF quartiles were positively associated with lower age, daily walking habit, cognition, diet quality, resilience, alcohol use and negatively associated with blood glucose levels, weight loss, body weight (BW) and falls. Polyunsaturated to saturated fat ratio and berry intake were also associated with PF. In a linear regression model PF was positively associated (p < .001, adjusted R2 = .560) with MeDi, cognition, resilience, vitality (RAND-36), and negatively with age and BW. Conclusion: MeDi, exercise, resilience, cognition, use of alcohol, fat quality and lower age were positively associated with PF in the oldest-old men. Weight loss, falls and interestingly BW were negatively associated with PF.