The present invention concerns a SAPO-34 molecular sieve and method for preparing the same, whose chemical composition in the anhydrous state is expressed as: mDIPA.(SixAlyPz)O2, wherein, DIPA is diisopropylamine existing in cages and pore channels of said molecular sieve, wherein m is the molar number of diisopropylamine per one mole of (SixAlyPz)O2, and m is from 0.03 to 0.25; x, y, z respectively represents the molar number of Si, Al, P, and x is from 0.01 to 0.30, and y is from 0.40 to 0.60, and z is from 0.25 to 0.49, and x+y+z=1. The SAPO-34 molecular sieve can be used as catalysts for acid-catalyzed reaction or oxygenate to olefins reaction.