The present invention provides an aptamer that bonds to autotaxin, said aptamer including a nucleotide sequence represented by the formula GWAACAGGUUUUGCU (SEQ ID NO: 42) (in the formula, W is A or U, and uracil can be thymine), and being one of the following: (a) the aptamer, wherein in the nucleotide included in the aptamer, (i) the 2' position of the ribose in each pyrimidine nucleotide is a fluorine atom, and (ii) the 2' position of the ribose in each purine nucleotide is a hydroxy group； or (b) the aptamer from (a), wherein (i) the fluorine atoms at the 2' position of the ribose in each pyrimidine nucleotide are each independently unsubstituted or substituted with an atom or a group selected from the group consisting of a hydrogen atom, a hydroxy group, and a methoxy group, and (ii) the hydroxy groups at the 2' position of the ribose in each purine nucleotide are each independently unsubstituted or substituted with an atom or a group selected from the group consisting of a hydrogen atom, a methoxy group and a fluorine atom.
