An assembly for mounting a kitchen extractor hood to a vertical wall of a kitchen between a pair of hanging cabinets (2, 3) of the kitchen furniture, which have a given depth relative to the surface of the wall, said system comprising a kitchen extractor hood and a mounting system: - said kitchen extractor hood comprising: - an extraction motor unit configured to extract the air; - filter devices for filtering the extracted air; - a channel for ejecting the extracted air; and - a casing covering the extractor motor unit, the filter devices and the channel for ejecting the extracted air, the casing having an inverted-T shape, wherein the casing comprises a horizontal bar containing the filter devices and a vertical stem containing the extractor motor unit and the channel for ejecting the extracted air; - said mounting system comprising: - a first frame secured to the vertical wall of the kitchen, between the pair of hanging cabinets (2, 3), said first frame having means for supporting said extraction motor unit of the hood and adjustable projection for adjusting the position of said extraction motor unit relative to the wall, based on the depth of said hanging cabinets, said first frame comprising right-angled elements (10, 11) whose long vertical sides are fixed to the wall by expansion means (12, 13, 14); - said right-angled elements (10, 11) of said first frame comprising protruding overhanging short sides (15, 16), perpendicular to the wall of the kitchen, said short sides (15, 16) forming a bracket supporting said extraction motor unit positioned on it; wherein said mounting system comprises: - a second frame fixed above said first frame, said second frame having means (20, 21) receiving and holding the casing of the hood based on the position of the extractor motor unit on the bracket with respect to the wall of the kitchen. - said kitchen extractor hood comprising: - an extraction motor unit configured to extract the air; - filter devices for filtering the extracted air; - a channel for ejecting the extracted air; and - a casing covering the extractor motor unit, the filter devices and the channel for ejecting the extracted air, the casing having an inverted-T shape, wherein the casing comprises a horizontal bar containing the filter devices and a vertical stem containing the extractor motor unit and the channel for ejecting the extracted air; - an extraction motor unit configured to extract the air; - filter devices for filtering the extracted air; - a channel for ejecting the extracted air; and - a casing covering the extractor motor unit, the filter devices and the channel for ejecting the extracted air, the casing having an inverted-T shape, wherein the casing comprises a horizontal bar containing the filter devices and a vertical stem containing the extractor motor unit and the channel for ejecting the extracted air; - said mounting system comprising: - a first frame secured to the vertical wall of the kitchen, between the pair of hanging cabinets (2, 3), said first frame having means for supporting said extraction motor unit of the hood and adjustable projection for adjusting the position of said extraction motor unit relative to the wall, based on the depth of said hanging cabinets, said first frame comprising right-angled elements (10, 11) whose long vertical sides are fixed to the wall by expansion means (12, 13, 14); - said right-angled elements (10, 11) of said first frame comprising protruding overhanging short sides (15, 16), perpendicular to the wall of the kitchen, said short sides (15, 16) forming a bracket supporting said extraction motor unit positioned on it; - a first frame secured to the vertical wall of the kitchen, between the pair of hanging cabinets (2, 3), said first frame having means for supporting said extraction motor unit of the hood and adjustable projection for adjusting the position of said extraction motor unit relative to the wall, based on the depth of said hanging cabinets, said first frame comprising right-angled elements (10, 11) whose long vertical sides are fixed to the wall by expansion means (12, 13, 14); - said right-angled elements (10, 11) of said first frame comprising protruding overhanging short sides (15, 16), perpendicular to the wall of the kitchen, said short sides (15, 16) forming a bracket supporting said extraction motor unit positioned on it; - a second frame fixed above said first frame, said second frame having means (20, 21) receiving and holding the casing of the hood based on the position of the extractor motor unit on the bracket with respect to the wall of the kitchen.