In this research, we propose a highly nonlinear photonic crystal fiber (HN-PCF) in optical coherence tomography window. Based on the finite difference method, different properties of highly nonlinear photonic crystal fibers are calculated. For the designed HN-PCF, flattened chromatic dispersion, low dispersion slope, low confinement loss, and high nonlinear coefficients are achieved, simultaneously. The proposed HN-PCF has the potential to obtain broadband continuum with high power and high longitudinal resolution in biological tissue.