A high-density Subscriber Identity Module (SIM) card package and a production method thereof are provided. The SIM card package includes a substrate, an Integrated Circuit (IC) chip, a bonding wire, and a mold cap. The substrate is a two-layer, a four-layer, a six-layer or an eight-layer high-density interlinked and packaged organic laminated substrate that is manufactured through an etching-back process, and a passive device and a crystal oscillator are provided on the organic laminated substrate. Two IC chips are provided side by side, or one of the IC chips is stacked with a third IC chip, the third IC chip being respectively connected to the organic laminated substrate and the IC chip under the third IC chip by the bonding wire. The IC chip, the passive device, and the crystal oscillator are adhered to the organic laminated substrate.