Abstract: In order to solve the poor adaptability of the traditional coal slime dense medium cyclone on the low density of dense medium suspension, the two gener al engineering parameters of applicability, commonality and amount of substance in TRIZ theory were used to analyze the technical contradiction of adaptbility and de nsity of dense medium suspension for coal slime separation. The three innovative principles of TRIZ theory, the local quality principle, physical or chemical parameters change principle, dynamic characteristics principle in TRIZ theory were used to improved design the structure of traditional slime dense medium cyclone. The authors p ut forward design plan for the new-type coal slime dense medium cyclone, which had the functions of dense medium concentrated in the first stage and separation in th e second stage. The structure of the new-type coal slime dense medium cyclone was designed and separation principle was introduced. The application results of the n ew-type coal slime dense medium cyclone in Nantong Coal Preparation showed that the new equipment could realize the coal slime effective separation to heavy mediu m suspension density of 1.10 ~ 1. 20 g/cm3and above, lower limit of separation was 0. 075 mm, coal slime separation precision was high, probable deviation Epvalue was 0. 072 5 g/cm3.