A lead-acid battery comprising a container having at least one cell chamber and a lid body for covering a top opening of the container. The lid body has on a top surface a recessed portion having therein an annular portion protruding upward and having, in an area of a bottom wall inside the protruding portion, an exhaust hole for exhausting gas from the cell chamber, wherein a guide passage for guiding gas from the exhaust hole to the outside is formed by joining the protruding portion with a joining portion provided on the lid body cover. An annular groove formed between the protruding portion and the vertical wall is covered with an outer periphery of the lid body cover 5 and the guide passage is isolated from the groove.