There is no reason. As a special administrative region of China, Hong Kong's financial and economic situation is very different from that of the Mainland. Therefore, the situation of Hong Kong's foreign exchange reserves needs to be analyzed and studied from many angles, and it cannot be simply compared with the mainland. Foreign exchange reserve is a creditor's right formally owned by a country or region and expressed in foreign currency. It refers to the foreign exchange assets that are centrally held by central banks and other government agencies and can be converted into foreign currency at any time. Under normal circumstances, the sources of foreign exchange reserves are trade surplus and capital inflow, which are concentrated in the domestic central bank to form foreign exchange reserves.