The purpose of this study is to investigate the relationship between costumes of court masque and the fashion trend at that time, by the analysis of the portraits. The period in this thesis is from Elizabeth I (1588-1603), until James I (1603-1625), when Inigo Jones was actively involved in court in masque, and when the traits of court masque began to appear in costume. The research material of this thesis is from the papers, costume design sketches, portraits and miniatures. As a result the costume of court masque which is the mixture of that of ancient Greece, Rome, middle age, and the exotic style of Ireland and Persian, had a great impact on the general fashion, and the unique pattern f costume became prevalent in the end of 16th and the early 17th century. This thesis might help us understand and special costume of that age and study the way how it come to have an influence on the fashion of the costume pertaining mainly to the privileged class.