Provided is a 
graphite-phase 
carbon nitride photocatalyst modified by basic 
bismuth carbonate. The 
graphite-phase 
carbon nitride photocatalyst comprises the chemical components of: in percent by 
mass,0.1-1.5% of basic 
bismuth carbonate and the balance 
graphite-phase 
carbon nitride, and the preparation method of the graphite-phase carbon 
nitride photocatalyst modified by the basic 
bismuth carbonate mainly comprises the steps of: adding 5-20 mg of 
bismuth citrate into every 30 g of 
urea, putting the 
urea and 
bismuth citrate into an agate 
mortar, performing full stirring, 
grinding and mixing for20 minutes, placing the obtained mixture in an 
alumina porcelain ark, then placing the porcelain ark in a 
muffle furnace for heat treatment, raising the temperature from a 
room temperature to 450-600DEG C at a heating rate of 2-30 DEG C per minute, performing 
thermal insulation for 1-2 hours, cooling to 
room temperature with the furnace, placing the obtained mixture in the agate 
mortar again, and 
grinding the mixture thoroughly into 
powder of 1-5 mum so as to obtain the graphite-phase carbon 
nitride photocatalyst modified by the basic 
bismuth carbonate. The graphite-phase carbon 
nitride photocatalyst has a preparation method with simple and easy operation, easily available raw materials, stable physical and chemical properties, environmental friendliness and high photocatalytic activity,and is beneficial to practical application and industrial production.