The present invention discloses a polyester, a preparation method therefor and use thereof. The polyester includes repeating units derived from the following components: a first component A, based on the total molar weight of the first component A, including: a1) 81-100 mol% of succinic acid, or an ester derivative thereof or an anhydride derivative thereof, and a2) 0-19 mol% of a dicarboxylic acid other than succinic acid, or an ester derivative thereof or an anhydride derivative thereof; a second component B: 1,4-butanediol; and a third component C: a dimer(1,4-butanediol); based on the total molar weight of the first component A, the molar content of the repeating unit -CH2CH2CH2CH2-O- in the third component C is 0.05-3.0 mol%. In the present invention, the molar content of the repeating unit -CH2CH2CH2CH2-O- in dimer(1,4-butanediol) is controlled to 0.05-3.0 mol%, and thus, the resin color of the polyester can be effectively improved.