The real-time discovery and accurate evaluation of oil-bearing properties of formation are affected by oil-emulsion drilling fluid. However, the quantitative accuracy of identification methods such as chromatography, mass spectrometry and spectrum without background value is low. One-dimensional T₂ nuclear magnetic resonance (NMR) method requires two analyses before and after the addition of relaxation reagents. For this reason, two-dimensional NMR T₁-T₂ method was adopted to test the oil-emulsion drilling fluid, brine with different salinity, three types of refined oil and five types of crude oil, and the interpretation chart of water, base oil and formation oil in the oil-emulsion drilling fluid was established. The evaluation model of formation oil content in the oil-emulsion drilling fluid was established by testing the oil-emulsion drilling fluid with different crude oil content. The lower detection limit of T₁-T₂ method was determined to be 200 ~ 750 mg/L by the test of white oil with different qualities. The interpretation chart and evaluation model were proved to be reliable by experimental simulation and actual drilling. Therefore, two-dimensional NMR T₁-T₂ maps can easily and clearly distinguish base oil and formation oil in oil-emulsion drilling fluid, and help realize the timely discovery and visual identification of oil-bearing properties of formation.