The purpose of this study is to examine the effects of a group art therapy program on social anxiety of late adolescents. The participants were 12 late-aged adolescents with social anxiety. Six participants were assigned to the experimental group and six participants were assigned to the control group. The group arts therapy program was conducted 6 times in total from November 18 to December 23, 2019 at once a week for 100 minutes for each section. The quantitative measure Korean version of the Social Anxiety Scale for Adolescents (K-SAS-A) was utilized. Wilcoxon signed-rank test for paired comparisons was conducted to analyze the quantitative data measured in this study. The qualitative analyses of participants’ behaviors through the whole sessions and their works were observed and analyzed. The results are as follows. First, the experimental group’s social anxiety was significantly reduced after conducting the group art therapy program. Second, there was positive change during the process of the group art therapy program of late-aged adolescents with social anxiety. Thus, this study concludes that the group art therapy program had effects on reducing the late-aged adolescents’ social anxiety.