A novel Antenna‐in‐Package with small size and low profile is designed based on Low Temperature Co‐fired Ceramic technology. In order to realize miniaturization and broadband in antenna part, a novel structure using double fractal antennas and air cavities is applied. A packaging cavity is designed for integrated with usable components and IC chips. The antenna operates at a center frequency of 2.4 GHz and the bandwidth is about 200 MHz. Its maximum gain is 5.6 dBi, and radiation efficiency is above 90% across the frequency passband. By adjusting the dimension parameters, a tradeoff between height and area can be made with its performance parameters constant, therefore the proposed Antenna‐in‐Package can easily adapt to different processes and performance.