The invention belongs to the technical field of computer database management, and particularly relates to a flexible transaction management method in key-value store data storage, which includes the following steps: when data is written, a coordinative module packages a request into a log and obtains the existing log position, the Parkes algorithm is used to write the log into the new log position, the position is recorded, the successful operation information is returned, and the data and the log position are written into the data storage; when the data is read, the coordinative module obtains the newest log position and checks whether the data is updated, if the data is updated, the data is read and returned to the user, and if the data is not updated, the log is read, and the data is then corrected and read and returned to the user. The flexible transaction management method improves the concurrency, the fault tolerance and the expansibility of the key-value store data storage, can narrow the limitation range of the transaction as much as possible under the circumstance that the system consistency is ensured, and improves the concurrency of the system; and the design of the flexible transaction has high positive function in improving the flexibility and the adaptability of the database transaction.