ObjectiveTo assess nutrition knowledge related to osteoporosis and calcium, osteoporosis health beliefs, dietary calcium intake and household food insecurity among adult women in Vietnam. MethodsTwo hundred fifty-one women aged 30–65 years living in a rural district in Hanoi -Vietnam were recruited. A questionnaire was used to collect information on nutrition knowledge related to osteoporosis and calcium intake, health beliefs, household food security, and dietary calcium intake. Data analysis included descriptive statistics and regressions. ResultsMajority of the participants did not know calcium recommendations (95%) and recommended daily servings of calcium-rich foods (60%). In addition, majority of the participants (83.7%) were not aware of osteoporosis risk factors. Slightly less than half of the participants (46.2%) reported that they would have difficulties changing their current diets to consume more calcium rich foods. Half of the participants (50.4%) reported being food insecure, with 22% of them reporting having severe food insecurity. Mean dietary calcium intake was 534.5 mg/day, of which milk and dairy products contributed only 4%. Nutrition knowledge, perceived benefits, and self-efficacy were positively associated with calcium intake (p < 0.05); whereas perceived barriers and severe food insecurity were significantly associated with low dietary calcium intake (p < 0.05). ConclusionsThe results of this study showed calcium intake among the participating Vietnamese women was lower than the national recommendation, indicating the need for nutrition programs and promotions to increase calcium intake. These programs should aim at increasing awareness on national calcium recommendations and skills to obtain and consume calcium-rich foods while considering development of safety nets for food insecure households, as pertaining to adequate dietary calcium intake.