- Kanazawa University
- Kandilli Observatory and Earthquake Research Institute
- Kansas State University
- KapScience LLC
- Kapteyn Astronomical Institute [Groningen]
- Karadeniz Technical University
- Karl-Franzens-Universität Graz
- Karlsruhe Institute of Technology = Karlsruher Institut für Technologie
- Karpagam Academy of Higher Education
- Kassel Institute for Sustainability
- Kavli Institute for Particle Astrophysics and Cosmology
- Kazan Federal University
- Keele University [Keele]
- Key Laboratory for the Structure and Evolution of Celestial Objects
- Key Laboratory of Atmospheric Chemistry [Beijing]
- Key Laboratory of Microwave Remote Sensing
- Key Laboratory of of Optical Astronomy
- Key Laboratory of Space Ocean Remote Sensing and Application
- Key Laboratory of Tropical Marine Bio-resources and Ecology
- Khalifa University
- Kharkov National University
- Kiepenheuer-Institut für Sonnenphysik
- Kindai University
- KinetX Aerospace Inc.
- King Abdullah University of Science and Technology [Saudi Arabia]
- King County Water and Land Resources Division
- King‘s College London
- KLA TENCOR
- Klaus-Tachira-Laboratory for Cosmochemistry
- Klimatologie, Klimadynamik und Klimawandel [Giessen]
- Knightwerx
- K. N. Toosi University of Technology
- Kobe University
- Kochi Institute for Core Sample Research
- Kochi University of Technology
- Koç University
- KOEGL Space GmbH
- Kola Science Center of Russian Academy of Sciences
- Konkoly Observatory
- Korea Advanced Institute of Science and Technology
- Korea Astronomy and Space Science Institute
- Korea Institute of Geoscience and Mineral Resources
- Korea Polar Research Institute
- Korea University [Seoul]
- KTH Royal Institute of Technology [Kista]
- KTH Royal Institute of Technology [Stockholm]
- KTH School of Electrical Engineering
- Kuopio Unit [FMI]
- Kwame Nkrumah University of Science and Technology
- Kwansei Gakuin University
- Kyoto Sangyo University
- Kyoto University
- Kyrgyz National University of Jusup Balasagyn
- Kyung Hee University
- Kyushu University
- Kyusyu University