A preparation method for a triptyl polymer separation membrane, wherein, it comprises the following steps: Take triptycene compound containing active group, dichloride compound and diamino compound containing ether bond as monomers, and conduct polymerization in aprotic organic solvent in the presence of acid-binding agent; pour the obtained polymer solution into deionized water for precipitation after the reaction, filter out precipitates and wash with methanol and dry to get triptyl polymer; the triptycene compound containing active group is the multi-amino-substituted triptycene compound or its derivative; Dissolve the triptyl polymer in aprotic organic solvent to produce a membrane-casting solution, apply the solution on support and dry to get a triptyl polymer separation membrane. characterized in that the dichloride compound is any one selected from oxalyl chloride, malonyl chloride, succinyl chloride, glutaryl chloride, adipoyl chloride, 1, 7-pimeloyl chloride, azelaoyl chloride, hexafluoro glutaryl chloride, sebacoyl chloride, 1,8-suberoyl chloride, terephthaloyl chloride, isophthaloyl chloride, o-phthaloyl chloride, cyclohexyl-1,4-dicarboxyl chloride, trimesoyl chloride, fumaryl chloride, tetrafluoro terephthaloyl chloride, hexafluoro glutaryl chloride, dodecanedioyl dichloride, 1,8-suberoyl chloride, 2,6-chloroformyl pyridine, 1,4-phenylene diacryloyl chloride, trans-3,6-endo-methylene-1,2,3,6-tetrahydrophthaloyl chloride, 5-amino-2,4,6-triiodo-1,3-benzenedicarboxylic acid acyl chloride, azobenzene-4,4'-dicarbonyl dichloride, 4,4'-biphenyldicarbonyl chloride, trans-cyclobutane-1,2-dicarbonyl dichloride, 1,4-phenylene diacryloyl chloride and bisphenol A bis(chloroformate), and in that the diamino compound containing ether bond is any one selected from bis(3-aminopropyl) ether, 3,4-oxydianiline, resorcinol diglycidyl ether, 4,4'-oxydianiline, neopentyl glycol bis(4-aminophenyl) ether, 1,3-bis(4-aminophenoxy)benzene, N-methyl-N-(4-aminophenoxy ethyl)-4-aminophenyl ethanamine, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 2,2'-diamino glycol diphenyl ether, 1,8-diamino-3,6-dioxaoctane, bis[4-(3-aminophenoxy)phenyl] sulfone, 1,4-butanediol bis(3-aminocrotonate), 4,4"-diamino-p-terphenyl, 2,2-bis[(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(trifluoromethyl)-4,4-diaminodiphenyl ether, 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene, 1,4-bis(2-trifluoromethyl-4-aminophenoxy)benzene and 2,2-bis[4-(4-aminophenoxy)phenyl]propane. Take triptycene compound containing active group, dichloride compound and diamino compound containing ether bond as monomers, and conduct polymerization in aprotic organic solvent in the presence of acid-binding agent; pour the obtained polymer solution into deionized water for precipitation after the reaction, filter out precipitates and wash with methanol and dry to get triptyl polymer; the triptycene compound containing active group is the multi-amino-substituted triptycene compound or its derivative; Dissolve the triptyl polymer in aprotic organic solvent to produce a membrane-casting solution, apply the solution on support and dry to get a triptyl polymer separation membrane. the dichloride compound is any one selected from oxalyl chloride, malonyl chloride, succinyl chloride, glutaryl chloride, adipoyl chloride, 1, 7-pimeloyl chloride, azelaoyl chloride, hexafluoro glutaryl chloride, sebacoyl chloride, 1,8-suberoyl chloride, terephthaloyl chloride, isophthaloyl chloride, o-phthaloyl chloride, cyclohexyl-1,4-dicarboxyl chloride, trimesoyl chloride, fumaryl chloride, tetrafluoro terephthaloyl chloride, hexafluoro glutaryl chloride, dodecanedioyl dichloride, 1,8-suberoyl chloride, 2,6-chloroformyl pyridine, 1,4-phenylene diacryloyl chloride, trans-3,6-endo-methylene-1,2,3,6-tetrahydrophthaloyl chloride, 5-amino-2,4,6-triiodo-1,3-benzenedicarboxylic acid acyl chloride, azobenzene-4,4'-dicarbonyl dichloride, 4,4'-biphenyldicarbonyl chloride, trans-cyclobutane-1,2-dicarbonyl dichloride, 1,4-phenylene diacryloyl chloride and bisphenol A bis(chloroformate), and in that the diamino compound containing ether bond is any one selected from bis(3-aminopropyl) ether, 3,4-oxydianiline, resorcinol diglycidyl ether, 4,4'-oxydianiline, neopentyl glycol bis(4-aminophenyl) ether, 1,3-bis(4-aminophenoxy)benzene, N-methyl-N-(4-aminophenoxy ethyl)-4-aminophenyl ethanamine, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 2,2'-diamino glycol diphenyl ether, 1,8-diamino-3,6-dioxaoctane, bis[4-(3-aminophenoxy)phenyl] sulfone, 1,4-butanediol bis(3-aminocrotonate), 4,4"-diamino-p-terphenyl, 2,2-bis[(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(trifluoromethyl)-4,4-diaminodiphenyl ether, 1,3-bis(2-trifluoromethyl-4-aminophenoxy)benzene, 1,4-bis(2-trifluoromethyl-4-aminophenoxy)benzene and 2,2-bis[4-(4-aminophenoxy)phenyl]propane.