To provide a dust collecting unit capable of performing double filtration by cyclone method and filtration, and simplifying the internal structure of the body of a vacuum cleaner, and the body of the vacuum cleaner using it.

This dust collecting unit includes a cylindrical casing part 130, in which the air flowing in through an inlet forms a spiral flow inside, the upper part of which is opened, a cover 110 for opening and closing the upper part of the casing part, a filter 114 provided on the lower surface of the cover, formed like a cylinder having a fixed length, and adapted to suck air from the outside, filter off fine dust and discharge the same through the inside, and an exhaust duct 138 brought into close contact with the lower end part of the filter to discharge the air emitted from the filter to the outside of the casing part, and having an exhaust part 136 on the side surface of the easing part. The exhaust part of the easing part is provided on the lower part of the side surface of the casing part.