Extraction device ( 210,410) for use in kitchen ventilation systems, the extraction device (210,410) comprising: a filter assembly ( 235 j) for filtering cooking fumes ( C F) from a kitchen environment ( K E2), the filter assembly ( 235 j) comprising filter units ( 235 1,235 2,235 3,235 4) each one having, at opposite faces thereof, an input section for receiving the cooking fumes (C F) and an output section for providing discard air resulting from cooking fumes ( C F) filtering, and a hollow case for supporting the filter assembly ( 235 j), the case having on its top ( 225 T) an output opening ( 125 OUT) for allowing exhaustion of the discard air, wherein the case has on its bottom ( 225 B) an input opening ( 225 IN) for the passage of the cooking fumes ( C F) from below the extraction device, in that the filter units (235 1,235 2,235 3,235 4) are arranged in succession inside the case and along a longitudinal direction of the case, the input and output sections of each filter unit (235 1,235 2,235 3,235 4) facing said input ( 225 IN) and output (125 OUT) openings, respectively, thereby the cooking fumes (C F) passing through said input opening (225 IN) are intercepted and filtered by the filter units (235 1,235 2,235 3,235 4) and the corresponding discard air is exhausted through the output opening ( 125 OUT), wherein each filter unit (235 1,235 2,235 3,235 4) extends between a first side wall (225 S1) of the case ( 225 IN) and a second side wall (225 S2) of the case ( 225 IN) opposite said first side wall (225 S1), characterised in that the filter units (235 1,235 2,235 3,235 4) are arranged in alternate succession of first ( 235 1,235 3) and second ( 235 2,235 4) filter units, the first filter units ( 235 1,235 3) defining, in a view according to said longitudinal direction, a crossed arrangement with the second filter units (235 2,235 4), such that the input and output sections of each first filter unit (235 1,235 3) also face said first (225 S1) and second (225 S2) side walls, respectively, and the input and output sections of each second filter unit ( 235 2,235 4) also face said second ( 225 S2) and first ( 225 S1) side walls, respectively. a filter assembly ( 235 j) for filtering cooking fumes ( C F) from a kitchen environment ( K E2), the filter assembly ( 235 j) comprising filter units ( 235 1,235 2,235 3,235 4) each one having, at opposite faces thereof, an input section for receiving the cooking fumes (C F) and an output section for providing discard air resulting from cooking fumes ( C F) filtering, and a hollow case for supporting the filter assembly ( 235 j), the case having on its top ( 225 T) an output opening ( 125 OUT) for allowing exhaustion of the discard air, wherein the case has on its bottom ( 225 B) an input opening ( 225 IN) for the passage of the cooking fumes ( C F) from below the extraction device, in that the filter units (235 1,235 2,235 3,235 4) are arranged in succession inside the case and along a longitudinal direction of the case, the input and output sections of each filter unit (235 1,235 2,235 3,235 4) facing said input ( 225 IN) and output (125 OUT) openings, respectively, thereby the cooking fumes (C F) passing through said input opening (225 IN) are intercepted and filtered by the filter units (235 1,235 2,235 3,235 4) and the corresponding discard air is exhausted through the output opening ( 125 OUT), wherein each filter unit (235 1,235 2,235 3,235 4) extends between a first side wall (225 S1) of the case ( 225 IN) and a second side wall (225 S2) of the case ( 225 IN) opposite said first side wall (225 S1), characterised in that the filter units (235 1,235 2,235 3,235 4) are arranged in alternate succession of first ( 235 1,235 3) and second ( 235 2,235 4) filter units, the first filter units ( 235 1,235 3) defining, in a view according to said longitudinal direction, a crossed arrangement with the second filter units (235 2,235 4), such that the input and output sections of each first filter unit (235 1,235 3) also face said first (225 S1) and second (225 S2) side walls, respectively, and the input and output sections of each second filter unit ( 235 2,235 4) also face said second ( 225 S2) and first ( 225 S1) side walls, respectively.