Exhibit 21

Wholly Owned Subsidiaries and Joint Ventures

Wholly Owned Subsidiaries

Donaldson Australasia Pty. Ltd.
Wyong, Australia Ultrafilter Pty. Ltd.
Nunwaiding, Victoria, Australia Donaldson Filtration Österreich, GmbH
Wien, Austria Donaldson Sales Inc.
Barbados Donaldson Europe, b.v.b.a.
Donaldson Coordination Center, b.v.b.a.
Donaldson Belgie, b.v.b.a.
Leuven, Belgium Donaldson do Brasil
Equipamentos Ltda
Saõ Paulo, Brazil Donaldson Canada, Inc.
Athens, Ontario, Canada Donaldson Far East Ltd.
Hong Kong, S.A.R., China Shanghai Donaldson Filtration Co., Ltd.
Shanghai, China Donaldson (Wuxi) Filters Co., Ltd.
Wuxi, China Donaldson Czech Republic s.r.o.
Klasterec nad Ohri, Czech Republic Donaldson Industrial CR s.r.o.
Kadan, Czech Republic Ultrafilter s.r.o.
Prague, Czech Republic Donaldson Scandinavia a.p.s.
Horsholm, Denmark Ultrafilter a.p.s.
Salgelse, Denmark Donaldson France, s.a.s.
Bron, France Donaldson, s.a.s.
Domjean, France Financiere de Segur s.a.
Le Bozec Filtration & Systems, s.a.
Paris, France Ultrafilter s.a.s.
Vigny, France Donaldson GmbH
Torit DCE GmbH
Dulmen, Germany Donaldon Filtration Deutschland GmbH
Haan, Germany Donaldson Deutschland Holding GmbH
Quality Air GmbH
Haan, Germany Ultratroc GmbH
Flensburg, Germany Ultrafilter Kft.
Budapest, Hungary Donaldson India Filter Systems Pvt. Ltd.
New Delhi, India P.T. Donaldson Systems Indonesia
P.T. Donaldson Filtration Indonesia
Jakarta, Indonesia Donaldson Italia s.r.l.
Ostiglia, Italy Nippon Donaldson Ltd.
Tokyo, Japan Donaldson Company Inc. (Luxembourg) SCS
DLXH S.a.r.l.
Luxembourg City, Luxembourg

Donaldson Filtration
(Malaysia) Sdn. Bnd.
Selangor Darul Ehsan, Malaysia Donaldson, S.A. de C.V.
Donaldson Servicio Industrial S. de R.L. de C.V.
Prestadora de Servicios Aguascalientes, S. de R.L. de C.V.
Diemo S.A. de C.V.
Aguascalientes, Mexico Donaldson Torit, B.V.
Donaldson Nederland B.V.
Wormerveer, Netherlands Ultrafilter B.V.
Nieuwegein, Netherlands Donaldson Filtration Norway a.s.
Moss, Norway Donaldson Filtration (Philippines) Inc.
Muntinlupa City, Philippines Donaldson Polska Sp. z.o.o.
Warsaw, Poland Donaldson Filtration (Asia Pacific) Pte. Ltd.
Singapore Ultrafilter s.r.o.
Bratislava, Slovakia Donaldson Filtration Systems (Pty) Ltd.
Cape Town, South Africa Donaldson Korea Co., Ltd.
Seoul, South Korea Donaldson Iberica Soluciones
en Filtracion, S.L.
Barcelona, Spain Donaldson Filtros Iberica S.L.
Madrid, Spain Ultrafilter S.L.
Terrassa, Spain Donaldson Schweiz GmbH
Aarau, Switzerland Donaldson Taiwan Ltd.
Taipei, Taiwan Donaldson Filtration (Thailand) Ltd.
Nothaburi, Thailand Donaldson (Thailand) Ltd.
Rayong, Thailand Donaldson Filtre Sistemleri
Ticaret Limited Sirketi
Istanbul, Turkey Donaldson Filter Components Ltd.
Donaldson UK Holding Ltd.
DFCH Ltd.
Hull, United Kingdom DCE Donaldson Ltd.
DCE Group Ltd.
Ultrafilter Ltd.
Leicester, United Kingdom Donaldson Capital, Inc.
ASHC, Inc.
Le Bozec Inc.
Minneapolis, MN USA

Joint Ventures

Advanced Filtration Systems, Inc.
Champaign, Illinois

Advanced Filtration Services, Inc.
Las Vegas, Nevada

Ultrafilter Pty. Ltd.
India

P.T. Panata Jaya Mandiri
Jakarta, Indonesia

Rashed Al-Rashed & Sons —
Donaldson Company Ltd.
Dammam, Saudi Arabia