Powder coating booth having a bottom surface, defining an inner space in which is insertable an element to be coated and comprising: - at least one spraying device adapted to spray coating powder on said element to be coated; - at least one collecting area defined in said inner space, on top of which said element to be coated passes to be coated with coating powder and in which the excess powder falls down; said booth being associated with first suction means for sucking and conveying air exiting said inner space; wherein said first suction means comprise at least one fan adapted to create a vacuum inside said booth in order to let the air flow from said booth towards a suction line adapted to convey the air and any residual powder; wherein the action of said first suction means prevents the powder being sprayed from coming out into the atmosphere through the slits on the walls of said booth; wherein said collecting area is associated with second suction means adapted to suck and convey said excess powder exiting said inner space; wherein said booth comprises a collecting device positioned in said collecting area to receive said excess powder, associated with said second suction means; wherein said collecting device comprises at least one conveying channel associated with said second suction means and adapted to convey said excess powder. - at least one spraying device adapted to spray coating powder on said element to be coated; - at least one collecting area defined in said inner space, on top of which said element to be coated passes to be coated with coating powder and in which the excess powder falls down; said booth being associated with first suction means for sucking and conveying air exiting said inner space; wherein said first suction means comprise at least one fan adapted to create a vacuum inside said booth in order to let the air flow from said booth towards a suction line adapted to convey the air and any residual powder; wherein the action of said first suction means prevents the powder being sprayed from coming out into the atmosphere through the slits on the walls of said booth; wherein said collecting area is associated with second suction means adapted to suck and convey said excess powder exiting said inner space; wherein said booth comprises a collecting device positioned in said collecting area to receive said excess powder, associated with said second suction means; wherein said collecting device comprises at least one conveying channel associated with said second suction means and adapted to convey said excess powder. said booth being associated with first suction means for sucking and conveying air exiting said inner space; wherein said first suction means comprise at least one fan adapted to create a vacuum inside said booth in order to let the air flow from said booth towards a suction line adapted to convey the air and any residual powder; wherein the action of said first suction means prevents the powder being sprayed from coming out into the atmosphere through the slits on the walls of said booth; wherein said collecting area is associated with second suction means adapted to suck and convey said excess powder exiting said inner space; wherein said booth comprises a collecting device positioned in said collecting area to receive said excess powder, associated with said second suction means; wherein said collecting device comprises at least one conveying channel associated with said second suction means and adapted to convey said excess powder.