An efficient and low-latency pixel data transmission module for the adaptive optics wavefront processor is presented. A fiber-based custom real-time pixel data transfer protocol is developed, which has the characteristics of long transmission distance, low-latency, and low-protocol overhead. The hardware part of the suite has been verified on different circuit boards with different field-programmable gate arrays. Obtained results demonstrate that the transmission and protocol processing delay are only 413.5 ns, the transmission bandwidth is 3.125 Gbps, and the error rate is less than 10−12. Under the same conditions of 156.25 MHz clock frequencies and length of transmission line, compared with the serial front panel data port protocol adopted by the thirty meter telescope and the european southern observatory, the transmission delay is significantly reduced by 2.82 times and has a remarkably low logic occupancy rate through our solution. Also, the method has been applied in several actual projects.