The invention relates to the field of molecular biology and the field of biological pharmacy, in particular to a Chinese brown frog skin cDNA library, a construction method thereof, and antibacterialpeptide gene having anti-clinical multidrug resistance activity selected from the cDNA library. The Chinese brown frog (Rana temporaria chensinensis, David) needed in constructing the library is artificially fed in Changbai Mountain area, the frog skin is collected before ovulation of the brown frog in autumn. The obtained features of the library are as follows: cDNA segments are about at 0.3-6 kb, titer of the library is 2.4*10<5> puf/mL, and the percentage of recombination reaches 99.4%. The broad-spectrum and efficient antibacterial peptide gene can be selected from the library, thereby theinvention provides evidences for developing and researching new antibacterial peptide on the one hand, and realizes the possibility of directionally changing the antibacterial spectrum, the solubility and the stability of the antibacterial peptide and the like on the other hand.