The invention discloses a shared content supervision method based on threshold key sharing and a block chain. The entity involved in the invention comprises a supervision department, a content provider, a block chain and a miner. The method specifically comprises the following steps: step 1, content permission snapshot; step 2, secret key distribution and recovery based on Shamir (t, n); step 3, content review based on transactions. according to the method and the system, the Shamir (t, n) threshold secret sharing is utilized, so that multiple parties can participate in content review together, the accuracy and fairness of content review executed by a supervision department are ensured, and collusion in the supervision department is effectively prevented. Besides, the whole review process is carried out in a block chain transaction mode, so that the defect of content supervision in a content sharing scheme based on a block chain at present is overcome, absolute disclosure and accuracy of the review records are ensured, and the public can conveniently audit and check the review records.