The year 2019 marks the 10th anniversary of the first report of ultrafast fiber laser mode-locked by graphene.This result has had an important impact on ultrafast laser optics and continues to offer new horizons.Herein,we mainly review the linear and nonlinear photonic properties of two-dimensional(2D)materials,as well as their nonlinear applications in efficient passive mode-locking devices and ultrafast fiber lasers.Initial works and significant progress in this field,as well as new insights and challenges of 2D materials for ultrafast fiber lasers,are reviewed and analyzed.