| J&A Jaidah Holdings | Construction |
| Jaber Bin Ali Al Hedfa and Partner | Financial Services |
| Jafco Aluminium & Steel Co. W.L.L | Industrial Manufacturing |
| Jaidah Group | Transport |
| Jaidah Heavy Equipment | Industrial Manufacturing |
| Jaidah Motors and Trading Company | Transport |
| Jamco Oil & Gas Qatar | Construction |
| Jamco Trading & Contracting Company WLL | Industrial Manufacturing |
| Jassim & Brothers Group Company W.L.L | Food and Beverages |
| JBK Ducab W.L.L. | Construction |
| Jeezan Trading, Transport & Industries Company | Transport |
| Jefferson International Trading & Contracting WLL | Construction |
| Jersey Group WLL | Industrial Manufacturing |
| Jet Travels | Leisure and Tourism |
| JNP Trading | Construction |
| JOINT GULF BUSINESS CO WLL | Oil and Gas |
| JSL GLOBAL | Transport |
| Jumah Al Hassan Trading and Contracting WLL | Conglomerates |
| K.B.F Trading & Contracting Company WLL | Construction |
| Kaar Technologies | Information Technology |
| Kamalco Calibration Solutions & Technical Services | Services |
| Kasimy Trading & Building Materials WLL Qatar | Conglomerates |
| Katara Hospitality | Leisure and Tourism |
| Kawaida Collaborative LLC - Qatar | Agriculture |
| KBAS Trading | Industrial Manufacturing |
