Abstract: A barbecue oven integrally made from a plane metal plate by punching at one time. Before used, the barbecue oven has a substantially flat cross-like pattern, including a bottom section, two long side sections and two short side sections. Multiple equally spaced elliptic holes are punched along four adjoining portions between the bottom section, long side sections and short side sections to form four bending lines, whereby the long and short side sections can be bent and securely connected by lateral engaging lugs thereof to form a box-like pattern defining a chamber. Multiple equally spaced circular holes are formed on the long and short side sections for ventilation. Support legs and ventilating slots are formed on the bottom section by punching. The support legs can be outward bent to support the barbecue oven and the ventilating slots can be selectively opened according to ventilation requirement. Bendable support portions and handle portions are formed on the short side-sections.