Polymer optical waveguides are fabricated on FR-4 substrates with UV-curable epoxy resins by the lithography method. The experiment results show that the typical loss and the crosstalk of the waveguides are less than 0.05 dB/cm and -60 dB, respectively. Moreover, the waveguides exhibit good misalignment tolerance. When there is a misalignment of ±5 μm at the input end, the increased insertion loss is less than 0.2 dB. A simulation model based on beam propagation method is used to investigate the mode power distribution, differential mode delay, and dependence of coupling efficiency on the launching conditions. The results indicate that using a fiber with core diameter comparable with the size of the waveguide excites fewer higher order modes and largely improves the waveguide performance. The fabricated optical polymer waveguides are promising as key devices for optical printed circuit board applications.