The invention relates to a growing trend prediction method of insulation performance of oil immersed transformers. The growing trend prediction method is characterized by including steps of establishing an oil chromatography monitoring foundation database of various oil immersed transformers and collecting oil chromatography monitoring data; arranging and cleaning the data to remove bad data, and ensuring effectiveness of the data; extracting retrieval data required for prediction, retrieving the oil chromatography monitoring data for data records complying with the prediction data; considering follow-up data of the retrieved data records as prediction data. Prediction automation can be realized, prediction reliability is ensured, prediction data of growing trend of the insulation performance of the oil immersed transformers can be reasonably and scientifically given, and the growing trend prediction method has the advantages of good effect, high applicability and application value and the like.