The present invention relates to a steam generator and a washing machine therewith. The present invention provides a steam generator including a water chamber for holding water, the water chamber having a heater mounted thereto for heating the water, a steam chamber for holding steam generated as the water chamber, and steam water is heated, a water supply line for supplying the water to the water chamber, and a steam discharge line for discharging steam from the steam chamber, wherein the water chamber has a vertical direction length (a vertical length) relatively greater than a horizontal direction length (a horizontal length); and a washing machine therewith.