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.
