User profiles constructed using vast network behaviour data are widely used in various fields. However, data island and central server capacity problems limit the implementation of centralised big data training. This paper proposes a user profile construction method, Fed-UserPro, based on federated learning, which uses non-independent and identically distributed unstructured user text to jointly construct user profiles. Latent Dirichlet allocation model and softmax multi-classification regression method are introduced into the federated learning structure to train data. The results show that the accuracy of the Fed-UserPro method is 8.69%–19.71% higher than that of single-party machine learning methods.