High salinity oil reservoir gas drive foaming agent composition and preparation method thereof

The invention relates to a high salinity oil reservoir gas drive foaming agent composition and a preparation method thereof, and mainly solves the problems that in an existing high salinity oil reservoir gas drive oil extraction process, foaming agents have poor salt resistance, can generate precipitate after encountering divalent ions, and the formed foams have low blocking capability. The foaming agent composition provided by the invention comprises the following components by mole fraction: 1 part of a long chain polyether nitrogen-containing compound and 0.1-50 parts of a long chain diphenyl ether sulfonate surfactant, wherein the long chain polyether nitrogen-containing compound has a general molecular formula shown as formula (I), the long chain diphenyl ether sulfonate surfactant has a general molecular formula shown as formula (II), the R1 is a fatty group of C10-C26, y is a chain segment sum, R4 and R5 are any one of alkyl and substituted alkyl of C1-C5, and R6 is alkylene of C1-C4. The technical scheme well solves the problems, and can be used for high salinity oil reservoir gas drive oil extraction.