PURPOSE: A process of preparing jelly(muk, Korean native name) of Eleocharis kuroguwai is provided by using starch extracted from Eleocharis kuroguwai as a main material. Whereby, the muk has increased color and stickiness. CONSTITUTION: Eleocharis kuroguwai is extracted and 5 to 20% by weight of the extracted Eleocharis kuroguwai is agitated with a small amount of salt at 50 to 80deg.C for 5 to 10min to get a coagulation, which is agitated at 80 to 90deg.C for 5 to 8min to be gel and then agitated once more for 2 to 5min.