The invention discloses an expression vector and application thereof in transgenic plant cultivation. The expression vector provided by the invention comprises an expression cassette A and an expression cassette B, wherein the nucleotide sequence of the expression cassette A is as shown in Sequence 6 in a sequence table; and the nucleotide sequence of the expression cassette B is as shown in Sequence 3 in the sequence table. The experiment proves that transgenic Arabidopsis thaliana is obtained by introducing the expression vector provided by the invention into wild type Arabidopsis thaliana. Compared with the wild type Arabidopsis thaliana, the transgenic Arabidopsis thaliana has obviously improved stress tolerance. Thus, the expression vector disclosed by the invention has important application value.