The properties of Highly Birefringent Microstructured Optical Fiber (HB-MOF) were studied by using a Finite-difference Frequency-domain method with Uniaxial Anisotropic Perfectly Matched Layer boundary condition (UPML-FDFD). Based on the numerical results,the influence of air-hole size and pitch length upon the birefringence,confinement loss and single-mode properties was analyzed. The properties of HB-MOF and the influence between them were considered synthetically. The mode-cutoff properties were studied using the effective area for the first time,and the wavelength range for single-mode operation can be obtained from this. The investigation is important to the design of HB-MOF with good performance.