<p>A Digital Subscriber Line (DSL) protection circuit includes a DSL and Plain Old Telephone Service (POTS) broadband-narrowband mixed signal port (4), a narrowband POTS port (5) and a splitter (6). The DSL and POTS broadband-narrowband mixed signal port (4) is connected with the narrowband POTS port (5) through the splitter (6). A line of an input terminal or an output terminal of the splitter (6) is connected in series with a restorable current-limiting device (2) which limits the abnormal current. The series-connecting line of the splitter (6) and the restorable current-limiting device (2) is connected in parallel with a voltage-limiting device (3) for bypassing the splitter (6). A line of the DSL and POTS broadband-narrowband mixed signal port (4) or a line of the narrowband POTS port (5) is connected in series with an overcurrent fusing device (1).</p>
