Collective communication is widely used in the field of high-performance computing research and engineering. In large-scale scientific and engineering computing, collective communication overhead accounts for a large proportion, sometimes even reaching 80% of the total messaging overhead. It is the performance bottleneck of the high-performance computing system. A NIC-based offloading mechanism supporting reduction operation was proposed. By embedding reduction operation logic components on NIC, the calculation of data during transmission was implemented, and the burden on the CPU and the communication delay were reduced. A 16-node protocol operation experiment was realized through the FPGA(field programmable gate array) platform, and the protocol operation in different node size was simulated based on the xNetSimPlus simulator. Experiments show that the method can effectively reduce the time of protocol operation in collective communication, and the proposed NIC offloading mechanism that supports reduction operation hardware offload can accelerate all-reduce operations by up to 2.71 times.