Abstract: Tight oil in Fuyu reservoir is an important alternative resource to ensure the sustainable development of Daqing oilfield, mainly distributed in Fuyu reservoirs in Changyuan, Sanzhao and Qijia-Gulong areas of Daqing. Boasting of high development potential, it is the reserve base for continuous and stable production of Changyuan peripheral oilfield. Through nearly 10 years of technical research and field tests, an effective development technology has been established. However, in terms of development efficiency, the horizontal well volume fracturing elastic exploitation is characterized with short high production period and fast decrease in production as a whole; the initial monthly decreasing rate is 20%~30%, and the annual decreasing rate is 40%~60%; after 2~3 years of elastic exploitation, the production wells encounter the difficulty in maintaining production under saturation pressure, and the elastic recovery rate is only 5.7%~8.2%. In order to improve the recovery rate of tight oil horizontal well development, indoor stress-sensitive physical simulation experiments and numerical simulation are carried out to determine the best time for energy replenishment, i.e., when the formation pressure coefficient is 0.60~0.65; CO₂ huff-puff is selected as the preferred recovery enhancement method; the injection volume is optimized to be 7 000~9 000 t/km, injection pressure to be 12~13 MPa, injection rate to be 130~150 t/d, and soaking time to be 40~50 d for the kilometer horizontal well section. The recovery enhancement in the single horizontal well field test ranges from 1.44% to 3.33%, with an average of 2.44% and an input-output ratio of 1:1.63 (oil price of 60), showing good technical and economic efficiency.