The present article describes novel highly nonlinear photonic crystal fibers (HN-PCFs) with flattened chromatic dispersion and low confinement losses. The proposed design has been simulated based on the finite-difference method with anisotropic perfectly matched layers absorbing boundary condition. It is proved that the design novel HN-PCFs is obtained a nonlinear coefficient greater than 45 W(-1) km(-1) and low dispersion slope -0.009 ps/(nm(2) km) at 1.55 mu m wavelength. In addition, results from numerical simulation show that the ultra-flattened dispersion of 0 +/- 0.65 ps/(nm.km) can be obtained in a 1.36-1.62 mu m wavelength range with confinement losses lower than 10(-7) dB/m in the same wavelength range. Another advantage of the proposed HN-PCFs is that it possessed modest number of design parameters. (C) 2008 Elsevier B.V. All rights reserved.