Automatic packaging machine for continuously packaging products each wrapped in a single envelope, comprising: - a conveyor that defines a conveying plane for conveying a continuous sheet of packaging material, in particular paper, along a conveying direction, said conveying plane comprising an entrance end of said continuous sheet and an exit end of a plurality of envelopes, each containing one of said products, wherein said entrance end of said conveyor can be associated with a feeding unit of a plurality of products in succession one after another and at a distance one from another on the continuous sheet fed on said conveying plane, - a feeding unit for feeding said continuous sheet on said conveying plane and that feeds said continuous sheet along a feeding plane that extends below said conveying plane, is orthogonal or substantially orthogonal to said conveying direction and is defined at said entrance end of said conveying plane, wherein said continuous sheet is fed along said feeding plane according to a feeding direction orthogonal or substantially orthogonal to said conveying plane and is deviated by a right angle or substantially a right angle in the passage from said feeding plane to said conveying plane, - a creasing unit of said continuous sheet to define a pair of longitudinal creases (C1, C2) in it for respectively folding a first longitudinal leaf that defines the back of said envelopes and a second longitudinal leaf that defines the closing flap of said envelopes, wherein said first longitudinal leaf and said second longitudinal leaf define a longitudinal central portion of said continuous sheet that defines the front of each of said envelopes and on which said products are fed arranged in succession one after another and at a distance one from another, wherein said packaging machine is characterised in that it comprises - at least one die-cutting unit for die-cutting at least one of said first longitudinal leaf, or in any case the longitudinal portion of said continuous sheet that defines said first longitudinal leaf, and said second longitudinal leaf, or in any case the longitudinal portion of said continuous sheet that defines said second longitudinal leaf, to die-cut in it the back and/or the profile of the back and the closing flap and/or the profile of the closing flap of each of said envelopes, respectively, wherein said die-cutting unit is arranged between said entrance end and said exit end of said conveying plane to act on said continuous sheet fed on said conveying plane. - a conveyor that defines a conveying plane for conveying a continuous sheet of packaging material, in particular paper, along a conveying direction, said conveying plane comprising an entrance end of said continuous sheet and an exit end of a plurality of envelopes, each containing one of said products, wherein said entrance end of said conveyor can be associated with a feeding unit of a plurality of products in succession one after another and at a distance one from another on the continuous sheet fed on said conveying plane, - a feeding unit for feeding said continuous sheet on said conveying plane and that feeds said continuous sheet along a feeding plane that extends below said conveying plane, is orthogonal or substantially orthogonal to said conveying direction and is defined at said entrance end of said conveying plane, wherein said continuous sheet is fed along said feeding plane according to a feeding direction orthogonal or substantially orthogonal to said conveying plane and is deviated by a right angle or substantially a right angle in the passage from said feeding plane to said conveying plane, - a creasing unit of said continuous sheet to define a pair of longitudinal creases (C1, C2) in it for respectively folding a first longitudinal leaf that defines the back of said envelopes and a second longitudinal leaf that defines the closing flap of said envelopes, wherein said first longitudinal leaf and said second longitudinal leaf define a longitudinal central portion of said continuous sheet that defines the front of each of said envelopes and on which said products are fed arranged in succession one after another and at a distance one from another, wherein said packaging machine is characterised in that it comprises - at least one die-cutting unit for die-cutting at least one of said first longitudinal leaf, or in any case the longitudinal portion of said continuous sheet that defines said first longitudinal leaf, and said second longitudinal leaf, or in any case the longitudinal portion of said continuous sheet that defines said second longitudinal leaf, to die-cut in it the back and/or the profile of the back and the closing flap and/or the profile of the closing flap of each of said envelopes, respectively, wherein said die-cutting unit is arranged between said entrance end and said exit end of said conveying plane to act on said continuous sheet fed on said conveying plane.