Exhibit 21.1

SUBSIDIARIES OF NATIONAL INSTRUMENTS CORPORATION

The following are subsidiaries of National Instruments Corporation, each with the state or other jurisdiction of its incorporation or organization noted:

Constellation International Holding BV, Netherlands

Digilent Information Technology (Shanghai) Co., Ltd., China

Digilent RO S.R.L., Romania

Digilent, Inc., a Washington corporation

Enterprise International Holding B.V., Netherlands

Gemni Holdings ULC, Canada

Hyperception, Inc., a Texas corporation

M2 SAS, France

Measurement Computing Corporation, a Delaware corporation

Measurement Computing GmbH, Germany

Micropross SAS, France

National Instruments (Czech Republic) s.r.o., organizacna zlozka, Czech Republic

National Instruments (Korea) Corporation, Republic of Korea

National Instruments (Thailand) Co., Ltd., Thailand

National Instruments AM LLC, Armenia

National Instruments Asia Minor Ölçüm Cihazlar Anonim Sirketi (Turkey), Turkey

National Instruments Asia Pacific Pte. Ltd., Singapore

National Instruments Australia Corporation, a Texas corporation

National Instruments Australia Pty Ltd., Australia

National Instruments Belgium N.V., Belgium

National Instruments Brazil Ltda, Brazil

National Instruments Canada Co., Nova Scotia

National Instruments Chile SpA, Chile

National Instruments Colombia SAS, Colombia

National Instruments Corporation (UK) Limited, United Kingdom

National Instruments Costa Rica Limitada (Ltda), Costa Rica

National Instruments de Mexico Servicios, S.A. de C.V., Mexico

National Instruments de Mexico, S.A. de C.V., Mexico

National Instruments Denmark ApS, Denmark

National Instruments Dresden GmbH, Germany

National Instruments Egypt LLC, Egypt

National Instruments Engineering GmbH, Germany

National Instruments Engineering GmbH & Co. KG, Germany

National Instruments Europe Corporation, a Texas corporation

National Instruments Finland Oy, Finland

National Instruments France Corporation, a Texas corporation

National Instruments France SAS, France

National Instruments Germany GmbH, Germany

National Instruments Gesellschaft m.b.H., Austria

National Instruments Hong Kong Limited, Hong Kong

National Instruments Hungary Kereskedelmi Korlátolt Felelősségű Társaság (National Instruments Hungary Kft.), Hungary

National Instruments Ireland Resources Limited, Ireland

National Instruments Israel Ltd., Israel

National Instruments Italy s.r.l., Italy

National Instruments Japan KK, Japan

National Instruments (Korea) Corporation, Republic of Korea

National Instruments Lebanon SARL, Lebanon

National Instruments Netherlands B.V., Netherlands

National Instruments New Zealand Limited, New Zealand

National Instruments Norway AS, Norway

National Instruments Philippines Inc., Philippines

National Instruments Poland Sp.Zo.o, Poland

National Instruments Romania s.r.l., Romania

National Instruments RUS LLC, Russia

National Instruments Scandinavia Corporation, a Texas corporation

National Instruments Singapore (Pte) Ltd, Singapore

National Instruments Spain, S.L., Spain

National Instruments Sweden A.B., Sweden

National Instruments Switzerland Corporation, a Texas Corporation

National Instruments Switzerland GmbH, Switzerland

NI France Holdings SAS, France

NI Hungary Software és Hardware Gyártó Korlátolt Felelősségű Társaság (NI Hungary Kft.), Hungary

NI Malaysia Sdn. Bhd., Malaysia

NI Southeast Asia Sdn. Bhd., Malaysia

NI Systems (India) Private Limited, India

NI Taiwan Corporation, Taiwan

Optimal Plus Germany GmbH, Germany

Optimal Plus Japan KK, Japan

Optimal Plus Ltd, Israel

Optimal Plus Philippines, Philippines

Optimal Plus Singapore PTE. Ltd, Singapore

Optimal Plus, Inc., a Delaware corporation

Phase Matrix, Inc., a California corporation

PT. National Instruments Indonesia, Indonesia

Quality Instrumentation Solutions, Inc., a Texas corporation

Shanghai NI Instruments Co. Ltd, China

Washington Holding & Finance B.V., Netherlands