Dialectical behavior therapy (DBT) is commonly used in the treatment of eating disorders (ED), yet few studies have examined the utility of DBT skills groups as an adjunct to evidence-based therapy for ED. Thus, we sought to examine the preliminary efficacy of a DBT skills group as an adjunct to Family-Based Treatment (FBT) for adolescent restrictive ED. Our preliminary pilot study included 18 adolescent girls ages 13-18 (M = 15.3, SD = 1.64) with restrictive ED, including Anorexia Nervosa (AN; N = 10), Atypical Anorexia Nervosa (AAN, N = 5), and Other Specific Feeding or Eating Disorder (OSFED; N = 3). All participants were enrolled in a 6-month, weekly DBT skills group and were concurrently receiving family-based treatment (FBT). Participants who completed the intervention experienced large effect sizes for increases in adaptive skills (Cohen's d = .71) and decreases in general dysfunctional coping strategies (Cohen's d = .85); and small to medium effect sizes for decreases in binge eating (Cohen's d = .40) and increases in percent expected body weight (% EBW; Cohen's d = .32). Finally, small effect sizes were evidenced in decreases in Global EDE-Q scores (Cohen's d = .26), EDE-Q restraint (Cohen's d = .29) and CDI scores (Cohen's d = .28). Our study presents promising preliminary data suggesting that adolescents with restrictive EDs receiving FBT could benefit from an adjunctive DBT skills group. Feasibility of and considerations for tailoring a DBT skills group to an outpatient ED treatment program are discussed.