Abstract: Gas condensate field of Yaha-23 is a deep condensate gas reservoir rich in condensate oil. The primary well completion technique of tubular conveying under-balanced perforation is conducted for reservoir protection, i.e., the perforating string is used as completion string for gas production or injection. The key of this technique lies on the sequence of packer setting and perforating, as well as the resulting problems. It is recommended to set the packer first and then perforate, and this plan is proved to be feasible by computation.