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Gully erosion process researches in recent 60 years were reviewed from the following aspects: definition comparison of gully erosion at home and aboard, critical model for the initiation of gully erosion, influence factors of gully erosion process, prediction model of gully erosion, and gully erosion research methodology. Key research fields were also proposed, including standardization and normalization of gully erosion monitoring;quantification of head ward erosion, sidewall collapsing erosion, and deep cut erosion in gully erosion process;quantification of sediment transport capacity and establishment of sediment transportation continuity equation in ephemeral gully and gully erosion process;soil erosion prediction model at slope scale which included the ephemeral gully erosion, and soil erosion prediction model at watershed scale which covered the gully erosion,；methodology research on gully erosion control.