Harmonia Vol IX No 1 tahun 2009.pdf The research problems are about Nyadran ceremonial processes, functions of Janggrung in that ceremony, and special musics in Janggrung offbeat. Results and discussions: (1) Nyadran ceremony can be concluded in ritual ceremony since day, time, place, head, and congregation chosen by Janggrung performance. (2) In Nyadran ceremony, Janggrung functioned as an emotional expression, an entertainment, means of communication, a symbolic representation, a physical response, a legalization of social and ritual religion organization, to keep continuity of culture, and as a prop of social integration. Moreover, Janggrung also functioned as extrication of one’s vow. Janggrung dancers (tledhek) who functioned in nyadran ceremony have several prohibition that cannot be broken, that is one of those dancers must be a virgin. (3) There are five special music to accompany Janggrung those are Lung Gandhung, Sekar Gandhung, Kinanthi Sandhung (called Kinanti Boyong by door-keeper), Cangklek and Kebogiro Gangsaran. The Beat that accompanies Janggrung is Javanese barreled orchestra Slendro without using garap ngajeng instrument. It is because there is no need to present lirihan instrument in Janggrung performance instrumentation.