Aimed at the shortage of classification evaluation for extra- low permeability reservoirs, several new techniques developed in reservoir research are introduced in recent years. Four classification evaluation parameters for extra-low permeability reservoir are proposed, including effective porosity, mainstream throat radius, movable fluid saturation and start-up pressure gradient. The reservoir classification evaluations are carried out to nine blocks. The results show that the seepage capacity and effective reservoir space could be effectively reflected. This classification method will be important to guide the oil/ gas field development.