Named entity recognition method and device, equipment and medium

The embodiment of the invention provides a named entity recognition method and device, equipment and a medium. The method comprises the following steps: acquiring a first training data set and a second training data set; performing character-level preprocessing, entity-level preprocessing and phrase-level preprocessing on the first training data set to obtain a third training data set, and constructing a sentence positive sample and a sentence negative sample based on the first training data set to obtain a fourth training data set; performing training by utilizing the third training data set and the fourth training data set to obtain a Transform language model; performing character-level preprocessing on the second training data set to obtain a fifth training data set; inputting the text corpus data in the fifth training data set into a Transform language model to obtain a labeling sequence, and training a conditional random field (CRF) model according to the labeling sequence to obtain a named entity recogn