A blockchain-based method for encrypting product information, wherein the method is applied to a producer, and comprises: unidirectionally generating (12, 32) a production encryption key according to a unique secret code of a product; encrypting (14, 34) production information of the product according to the production encryption key, to generate production information encryption data; generating a production information query identifier according to the production encryption key, comprising unidirectionally generating a first distribution key according to the production encryption key, and unidirectionally generating the production information query identifier according to the first distribution key; and writing a production information set to a blockchain, wherein the production information set comprises the production information query identifier and the production information encryption data, wherein the writing a production information set to a blockchain comprises: encrypting the first distribution key according to a first public key, to generate first distribution key encryption data, wherein the first public key is a distribution public key of a first distributor; unidirectionally generating a first distribution key query identifier according to the first public key; and writing a production information set to the blockchain, wherein the production information set comprises the first distribution key query identifier, the production information query identifier, the first distribution key encryption data, and the production information encryption data. unidirectionally generating (12, 32) a production encryption key according to a unique secret code of a product; encrypting (14, 34) production information of the product according to the production encryption key, to generate production information encryption data; generating a production information query identifier according to the production encryption key, comprising unidirectionally generating a first distribution key according to the production encryption key, and unidirectionally generating the production information query identifier according to the first distribution key; and writing a production information set to a blockchain, wherein the production information set comprises the production information query identifier and the production information encryption data, wherein the writing a production information set to a blockchain comprises: encrypting the first distribution key according to a first public key, to generate first distribution key encryption data, wherein the first public key is a distribution public key of a first distributor; unidirectionally generating a first distribution key query identifier according to the first public key; and writing a production information set to the blockchain, wherein the production information set comprises the first distribution key query identifier, the production information query identifier, the first distribution key encryption data, and the production information encryption data. encrypting the first distribution key according to a first public key, to generate first distribution key encryption data, wherein the first public key is a distribution public key of a first distributor; unidirectionally generating a first distribution key query identifier according to the first public key; and writing a production information set to the blockchain, wherein the production information set comprises the first distribution key query identifier, the production information query identifier, the first distribution key encryption data, and the production information encryption data.