An aptamer that binds to FGF2, which comprises a nucleotide sequence represented by the following formula (wherein uracil is optionally thymine), and which is the following (a) or (b): N 1 GGAN 2 ACUAGGGCN 3 UUAAN 4 GUN 5 ACCAGUGUN 6 (formula 1) N 1 and N 6 are each independently any 0 to several bases, N 2 , N 3 , N 4 and N 5 are independently any one base, (a) an aptamer wherein, in the nucleotides contained in the aptamer, (i) the 2'-position of the ribose of each pyrimidine nucleotide is a fluorine atom, (ii) the 2'-position of the ribose of each purine nucleotide is a hydroxy group; (b) the aptamer of (a), wherein (i) the fluorine atom at the 2'-position of the ribose of each pyrimidine nucleotide is independently unsubstituted, or substituted by an atom or group selected from the group consisting of a hydrogen atom, a hydroxy group and a methoxy group, (ii) the hydroxy group at the 2'-position of the ribose of each purine nucleotide is independently unsubstituted, or substituted by an atom or group selected from the group consisting of a hydrogen atom, a methoxy group and a fluorine atom. N 1 and N 6 are each independently any 0 to several bases, N 2 , N 3 , N 4 and N 5 are independently any one base, (a) an aptamer wherein, in the nucleotides contained in the aptamer, (i) the 2'-position of the ribose of each pyrimidine nucleotide is a fluorine atom, (ii) the 2'-position of the ribose of each purine nucleotide is a hydroxy group; (b) the aptamer of (a), wherein (i) the fluorine atom at the 2'-position of the ribose of each pyrimidine nucleotide is independently unsubstituted, or substituted by an atom or group selected from the group consisting of a hydrogen atom, a hydroxy group and a methoxy group, (ii) the hydroxy group at the 2'-position of the ribose of each purine nucleotide is independently unsubstituted, or substituted by an atom or group selected from the group consisting of a hydrogen atom, a methoxy group and a fluorine atom. (a) an aptamer wherein, in the nucleotides contained in the aptamer, (i) the 2'-position of the ribose of each pyrimidine nucleotide is a fluorine atom, (ii) the 2'-position of the ribose of each purine nucleotide is a hydroxy group; (i) the 2'-position of the ribose of each pyrimidine nucleotide is a fluorine atom, (ii) the 2'-position of the ribose of each purine nucleotide is a hydroxy group; (b) the aptamer of (a), wherein (i) the fluorine atom at the 2'-position of the ribose of each pyrimidine nucleotide is independently unsubstituted, or substituted by an atom or group selected from the group consisting of a hydrogen atom, a hydroxy group and a methoxy group, (ii) the hydroxy group at the 2'-position of the ribose of each purine nucleotide is independently unsubstituted, or substituted by an atom or group selected from the group consisting of a hydrogen atom, a methoxy group and a fluorine atom. (i) the fluorine atom at the 2'-position of the ribose of each pyrimidine nucleotide is independently unsubstituted, or substituted by an atom or group selected from the group consisting of a hydrogen atom, a hydroxy group and a methoxy group, (ii) the hydroxy group at the 2'-position of the ribose of each purine nucleotide is independently unsubstituted, or substituted by an atom or group selected from the group consisting of a hydrogen atom, a methoxy group and a fluorine atom. <EOS>