Three lignin-based emulsifiers were selected to explore the effects of surface activity and dosage of different emulsifiers on their 1d and 5d storage stability, D10, D50 and D90 characteristic particle size, standard viscosity and Engla viscosity. At the same time, the correlation between characteristic particle size and viscosity of emulsified asphalt and its 1d and 5d storage stability was studied by grey correlation entropy and linear correlation analysis methods. The results show that when the emulsifier content is 3%, the storage stability of 1d and 5d, the characteristic particle size of D10, D50 and D90, the standard viscosity and Engla viscosity of emulsified asphalt are the best and tend to be stable. The stronger the hydrophilicity and polarity of the hydrophilic group of emulsifier molecule, the stronger its surface activity, which is more conducive to the stability of emulsified asphalt. The order of grey entropy correlation between characteristic particle size and 1d and 5d storage stability of emulsified asphalt is D90 > D50 > D10, and Engla viscosity and standard viscosity have the highest grey entropy correlation with 1d and 5d storage stability respectively, and the linear correlation of the three is highly positive; Comprehensive correlation analysis of the relationship between particle size, viscosity and stability shows that D90 particle size has the highest correlation degree with the grey entropy of 1d and 5d storage stability of emulsified asphalt and shows a high positive correlation. D90 particle size can reflect the storage stability of emulsified asphalt to a certain extent.