The invention discloses a selective catalytic reduction denitrification catalyst prepared by a hydrothermal method, which is characterized by comprising the main raw materials of TiO2 particles, water, soluble salt of tungsten or soluble salt of molybdenum, soluble salt of copper or soluble salt of chromium and strong alkali. The invention also discloses a preparation process of the catalyst, which comprises the steps of firstly preparing a titanium dioxide nanotube loading various active substances by the hydrothermal method, and then washing with water, drying and burning to obtain a catalyst sample. The catalyst has favorable denitrification activity, selectivity and stability and extensive application prospect.