2020 The Authors. Food Science & Nutrition published by Wiley Periodicals, Inc. Eating disorders are among the most prevalent disorders in adolescence and can have negative consequences including poor quality of life, medical complications, and even death. This study addresses whether normal variations in personality relate to eating behavior and eating disorder symptomatology in adolescent girls. Participants were a near-representative sample of Australian adolescent girls (n = 1,676). Three personality traits (neuroticism, extraversion, and conscientiousness) were assessed at age 12 and again at age 14, and self-reported eating and weight management behaviors were assessed at age 14. After controlling for sociodemographic factors, higher levels of conscientiousness at age 12, and increases in conscientiousness between ages 12 and 14, were associated with greater fruit and vegetable consumption, a lower intake of high fat foods and high sugar drinks, less frequent meal skipping, better oral health, and decreased risk of partial syndrome bulimia nervosa at age 14. Higher neuroticism at age 12 was associated with more frequent meal skipping, and increases in neuroticism between ages 12 and 14 were associated with more frequent meal skipping and increased risk of partial syndrome bulimia nervosa at age 14. Extraversion was generally unrelated to eating and weight management behaviors. These findings provide evidence that normal variations in personality are related to eating behavior, oral health, and eating disorder symptoms during midadolescence.