To provide a lid for a beverage container having a straw insertion port forming means of a new cutting line format having a constitution which prevents a content in a container from spilling out to the outside of the container.

The lid for the beverage container has a groove-shaped rib that is fit to an edge of an opening of the beverage container, and an upper wall connected to an inner periphery side of the rib, and a laser-beam machined cutting line for inserting a straw into the container from the outside of the container and locking it is disposed at least at one spot on the upper wall. The laser-beam machined cutting line forms a non-penetrating fusion part having a thickness smaller than that of the upper wall all over the cutting line.