The present invention relates to the technical field of automatic splicing methods, in particular to an automatic splicing method at the end of a coil, comprising the following steps: attaching a tail mark to the end of the coil, and pasting a double-sided adhesive tape and a joint mark on the head of the coil , when the mark detector detects the tail mark, the PLC controller controls the coil material of the first unwinding mechanism and the coil material of the second unwinding mechanism to automatically pick up materials; when the mark detector detects the joint mark, the PLC controller Control the defective product discharge mechanism to discharge the finished products with joint marks. The invention can realize coil end detection, automatic splicing of two coils and discharge of defective products, realize maximum utilization of coil raw materials, waste coil raw materials from tens of meters to several meters or even tens of centimeters, and reduce It reduces 80-99% loss of coil raw materials, which greatly saves production costs. At the same time, it can smoothly discharge finished products with joint marks, with a high degree of automation and high processing efficiency.