Abstract: OBJECTIVE To study the prescription composition and influencing factors of total alkaloids of Coptis chinensis intragastric floating sustained release tablets. METHODS The in vitro release of total alkaloids from Coptis chinensis was used as an index to screen the prescription composition of the sustained release tablets. The effects of hydroxypropyl methylcellulose(HPMC), sodium alginate and sodium bicarbonate on the in vitro release of the tablets were investigated by single factor test. RESULTS The optimal formulation of total alkaloids of Coptis chinensis intragastric floating sustained release tablets was HPMC 13.4%, sodium alginate 26.6%, magnesium stearate 5.4%, stearic acid 42.0%, NaHCO₃ 10.6%. The dosage of HPMC and sodium bicarbonate significantly affected the in vitro release of total alkaloids of Coptis chinensis intragastric floating sustained release tablets. CONCLUSION HPMC and sodium alginate combined with the ratio of 1:2 as tablet hydrophilic gel skeleton have good release in vitro, and they interact with each other.