A connector includes an inlet port into which liquid is poured and which has a first flow path for the liquid, a liquid discharge port to which a tube body is connectable and which has a second flow path discharging liquid from the first flow path to the connected tube body, a gas discharge which discharges air in the first flow path, and a blocking device which, when the liquid is poured in the first flow path, temporarily stops the liquid flow. Use of the connector involves sealing an opening section of the liquid discharge port, pouring liquid in the inlet port, causing air in the first flow path to be discharged, temporarily stopping the flow of the liquid in the first flow path, unsealing the opening section of the liquid discharge port, connecting the tube body to the liquid discharge port, and resuming flow of the liquid.