To meet the rapid development of oilfield exploration and development, efficient exploration of low-permeability reservoirs has become the primary approach. The Changqing low-permeability reservoir exhibits characteristics such as low permeability, low porosity, low pore throat, and low oil recovery. Microemulsions, characterized by small particle size and low interfacial tension, have recently garnered significant research attention and found extensive applications in hydraulic fracturing and enhanced oil recovery in unconventional reservoirs. To enhance oil recovery of Changqing oilfield, a microemulsion containing gemini surfactant, laurate diethanolamide, isopropanol, and D-limonene was proposed. Subsequently, a nano-emulsion derived from the microemulsion was synthesized and assessed. The nano-emulsion has a particle size distribution below 30 nm and an interfacial tension of 0.001 mN/m, and it achieves a contact angle of 86.29° on treated glass surfaces with 0.3% microemulsion. Compared with 2.0% potassium chloride solution, the 0.3% microemulsion demonstrated improvement by 29.96% in oil recovery through imbibition. In dynamic water flooding tests, one pore volume of nano-emulsion and four pore volume of water yielded an increase of 12.04% in oil recovery when compared with an equivalent total volume of water injection. Having been applied in three water injection wells in the tight oil reservoir in Changqing oilfield, the average daily oil production of adjacent fourteen oil wells increased by 9.2%, the cumulative oil production increased by 178 t and the average water cut decreased by 8.1% after 5 months, signifying a substantial productivity boost. Hence, the nano-emulsion exhibits a promising prospect in enhancing oil recovery in low-permeability reservoirs.