The two-color ball is drawn by the lottery center in a unified way, and it is drawn every Tuesday, Thursday and Sunday on 2 1: 15. China welfare lottery "two-color ball" is a "lottery" welfare lottery jointly issued by China Welfare Lottery Issuance Management Center, which is distributed and sold nationwide. Distribute and sell through multi-channel computer network system, and hold lottery on TV regularly.

Before each lottery of the two-color ball, the sales data is stamped by the notary, and then the lottery number is determined by the lottery machine under his supervision. In the lucky draw, first shake out 6 red ball numbers, and then shake out 1 blue ball numbers. After each lottery, the lottery center and the provincial lottery institutions shall announce the lottery number, the total sales amount of the current period, the winning situation of each prize level and the fund balance of the prize pool to the public, and notify the sales outlets of the lottery results.