Many studies have reported magnesium's role in nutrition as a vital factor involved in bone health. However, not enough studies have evaluated magnesium (Mg) intakes in young women. In this study, we evaluated Mg intake in healthy adults and its relation with bone quality. A total of 484 healthy young women in their early 20s were enrolled into the study. Anthropometric measurements, dietary intake survey using 3-day dietary records, and the bone quality of the calcaneus using quantitative ultrasounds were obtained and analyzed. Average age, height, and weight of the subjects were respectively 20.20 years, 161.37 cm, and 54.09 kg, respectively. Also, the average broadband ultrasound attenuation, speed of sound (SOS), stiffness index (SI), and calcaneus T scores were 114.32 dB/MHz, 1,568.45 m/s, 95.23, and 0.36 g/cm(2), respectively. The subject's average intake of energy was 1,543.19 kcal, and the average Mg intake was 185.87 mg/day. Mg intake per 1,000 kcal of consumed energy in our subjects was 119.85 mg. Subjects consumed 63.11% of the recommended intake for Mg. Food groups consumed with high Mg content in our subjects included cereals (38.62 mg), vegetables (36.97 mg), milk (16.82 mg), legumes (16.72 mg), and fish (16.50 mg). The level of Mg intake per 1,000 kcal showed significant correlation to the SOS in the calcaneus (r = 0.110, p < 0.05) after adjustment for age, BMI, and percent body fat. In addition, the intakes of Mg from potatoes (p < 0.001), legumes (p < 0.05), and fungi and mushrooms (p < 0.05) positively correlated with the SOS of the calcaneus. In conclusion, the magnesium intake status of young Korean women aged 19-25 years is unsatisfactory. Improving dietary intake of Mg may positively impact bone quality in this population.