The subject of the work is a composition Vespers composed by Julije Bajamonti which is kept in manuscript in the Music archive of Split Cathedral. About the subject of the paper itself, composition Vespers composed by Julije Bajamonti, so far there is no knowledge. The aim of this paper is to gain insights into Bajamonti’s musical language, to find out how he composed the liturgical rite in music and what forms he used. Three methods of musical theory will be used in this paper. The first one is philological method; next one is analytical method and the last one is comparative method. Bajamonti’s composition Vespers contains seven movements: the first one is introductory invocation, then five psalms and at the end Magnificat. Bajamonti divides movements into multiple parts and groups them according to a particular tonality center. Every part includes one or more verses. Every movement and every part within the paragraph are rounded by the same tonal center. In addition to a common formal procedure of connecting different motives, it is necessary to point out constant change of instrumentation and texture in every movement.