The present invention discloses a composition for alleviating atopic dermatitis using a flower extract of citrus unshiu. When HaCaT cells are treated with the composition of the present invention, expressions of atopic dermatitis-related factors TARC, MCP-1, IL-8, IL-6 and MDC are inhibited in proportion to a treatment concentration, wherein the HaCaT cells are human keratinocyte cell lines treated with INF-&gamma and TNF-&alpha.COPYRIGHT KIPO 2018본 발명은 INF-γ와 TNF-α로 처리된 인간각질형성세포주인 HaCaT 세포에 처리될 때 처리 농도에 비례하여 아토피 피부염 관련 인자인 TARC, MCP-1, IL-8, IL-6 및 MDC 발현을 억제하는 활성을 가진 온주 밀감 꽃 추출물을 이용한 아토피 피부염 개선용 조성물을 개시한다.