Imbibition is an important mechanism for enhancing the recovery efficiency of tight oil reservoirs. Nanoparticles and nanobubbles can enter nano-sized pores to improve oil-water properties. Additionally, nanobubbles serve to replenish microscopic energy, making them an ideal system for enhancing imbibition and production in tight oil reservoirs. This paper takes the core from the Chang 6 reservoir in the Wuqi area as an example, comparing and studying the imbibition characteristics of an active nanofluid system (nanobubbles + nano SiO2 particles) and simulating the application effects in the field. Experimental results indicate that 0.1% active nanofluid can increase the water wettability of the core by 48.3% and reduce the oil-water interfacial tension by 17.8%, significantly lowering seepage resistance. Imbibition tests confirmed that the active nanofluid enhances the imbibition effect, with a 0.1% active nanofluid imbibition recovery rate 5.5 percentage points higher than that of formation water, and 2.4 percentage points higher than that of SiO2 nanofluid. The permeability increase effect of the new system with nano-bubbles is 1.76 times that of pure SiO2 nano-fluids .Furthermore, the new nanofluid system shows differences in the pore utilization patterns of oil-wet and water-wet reservoirs, where oil-wet reservoirs mainly utilize medium pores (27.8 < r ≤ 203.9 nm) for oil, while water-wet reservoirs primarily utilize large pores (r ≥ 126.9 nm) for oil.Simulation results indicate that injecting active nanofluids has a significant effect within three years, reducing water content from 60% to 40%. Compared to cases without measures, daily oil production can increase by more than 1.5 times. Additionally, the recovery degree after six years of simulated adjustments is 15% higher than conventional water flooding. This study provides valuable references for oil recovery through imbibition in tight and shale ultra-low permeability reservoirs.