If I immigrate to Hong Kong now, can my personal social security be refunded? How much can I refund?

You can't surrender, but you can choose whether to continue to pay. As long as you reach retirement age, you can decide how to handle your old-age insurance account according to whether your contribution reaches 15. If it has reached 15, you can enjoy a monthly pension. If it is less than 15, the individual payment principal and interest can be refunded in full.