The invention relates to a system and method for controlling cold rube-rolling mill tube seam detection. The system comprises a PLC, an HMI, a main motor speed adjusting device, an electromagnetic valve relay, an inlet and outlet chuck hydraulic device, an eddy annular tube seam detection instrument (1), a feeding-in motor driving device and a host encoder, wherein the input end of the PLC is respectively connected with the HMI, the eddy annular tube seam detection instrument (1) and the feeding-in motor driving device, the output end of the PLC is respectively connected with the main motor speed adjusting device and the inlet and outlet chuck hydraulic device through the electromagnetic valve relay, and the input end of the feeding-in motor driving device is connected with the host encoder. According to the system and method for controlling the cold rube-rolling mill tube seam detection, the error caused by manual observation can be avoided, the production efficiency is comprehensively improved, and the high-speed full-automatic production of a tube-rolling mill can also be achieved.