The invention discloses a backup file recovery method for a heterogeneous database. The method includes the following steps that normalized transformation is conducted on data in the heterogeneous database, a DELTA compression algorithm of K-Medoids clustering is adopted for clustering preprocessing of data blocks, and the data blocks high in similarity are divided into a class; the DELTA compression algorithm is used for compression of the data blocks of the same class, data recovery is conducted based on 'SQL reappearance method', a recovery-end database version is read according to the configuration file, according to the transformation rule, a metadata model is transformed into SQL statements which a database with the corresponding version supports, after data consistency detection, the SQL statements are introduced into the database, and the stable backup and recovery functions of the heterogeneous database are achieved. Through extension of a mapping rule, multiple source databases can be supported, backup of the heterogeneous database is achieved, efficient file compression is supported, and the cost of backup is reduced.