Optical receiving antennas play a pivotal role in enhancing the communication quality of visible light communication (VLC) systems. In this study, we propose an innovative optical receiving antenna based on free-form surfaces. Initially, the layout scheme for the LED array is meticulously optimized to ensure uniform indoor illumination. Subsequently, a three-piece integrated optical receiving antenna is designed using XY polynomial free-form surfaces with the primary objectives of amplifying the optical gain, augmenting the received power, and elevating the signal-to-noise ratio (SNR). To further validate the efficacy of the proposed optical receiving antenna, an indoor VLC channel model is established, and its performance is rigorously analyzed. Experimental outcomes reveal that the mean square error of indoor illumination stands at 113.3 lx, the optical gain of the free-form optical receiving antenna reaches an impressive 11.29, the semiregular field of view spans 35.2°, the average received power amounts to 6.1251 dBm, the average SNR attains 84.7054 dB, and the radius of the optical spot is a mere 1.5 mm. Consequently, the optimized free-form optical receiving antenna can guarantee high-speed and stable communication within indoor VLC systems, thereby furnishing crucial technical support for the advancement of VLC communication technology.