Traditional UHF RFID tags follow the form-factor of a bar-code label. Constrained by the limited design space, the antennas are hard to be optimized and customized for specific product packages, especially for the packages containing RF non-friendly contents. In this paper, we proposed two 3-D and package conformal antenna designs. These antennas can either enhance the gain in the desired direction, or beam the radiation into the direction with less obstructions and shielding. The antenna elements can be fabricated on the same substrate and embedded into different facets of the package. When being folded into boxes, the 3-D antenna geometry will be placed into the right locations. Both HFSS simulation and field tests demonstrate that the performance of the proposed antennas is significantly enhanced.