Super-adhesive composite modified emulsified asphalt is prepared from matrix asphalt, SBS modifier, viscosity reducer, cationic emulsifier, hydrochloric acid, water and SBR modifier. The method includes the steps of firstly, heating matrix asphalt, adding SBS modifier to be stirred, evenly dispersing SBS modifier in matrix asphalt, and preparing SBS modified asphalt; secondly, heating SBS modified asphalt, adding viscosity reducer, dispersing viscosity reducer to SBS modified asphalt, and preparing SBS modified asphalt used for emulsification; thirdly, placing SBS modified asphalt which is prepared in the second step and used for emulsification in an asphalt tank of an emulsification device to be emulsified; fourthly, adding cationic emulsifier and water into a liquid soap tank of the emulsification device to prepare liquid soap; fifthly, adding concentrated hydrochloric acid to heat liquid soap; sixthly, emulsifying SBS modified asphalt used for emulsification and liquid soap in the liquid soap tank through a colloid mill; seventhly, externally adding SBR modifier to be mixed with emulsification asphalt at a normal temperature for secondary modification. Composite modification is conducted through SBS and SBR modifier, the emulsified asphalt is good in stability, and viscosity of asphalt generated after demulsification is large.