| Carnegie Mellon University Qatar | Education |
| Casadel Gelato | Food and Beverages |
| CASTELLO - Cast Aluminium Company-Qatar | Industrial Manufacturing |
| Castle Constructions WLL | Construction |
| Castle for Building Materials Company | Industrial Manufacturing |
| Cedars Motors & Trading Co WLL | Conglomerates |
| Celerity Shipping & Forwarding Co WLL | Transport |
| Central Ventilation System Co WLL | Industrial Manufacturing |
| Central Ventilation Systems Co. WLL | Construction |
| Century Hotel - Doha | Leisure and Tourism |
| Century Trading & Contracting WLL | Oil and Gas |
| Century Trading and Contracting WLL Qatar | Services |
| CEVA Logistics Qatar WLL | Transport |
| Challenger Limousine & Rent a Car | Transport |
| Charlotte Trading & Contracting | Food and Beverages |
| Chebli Machinery and Construction Company | Construction |
| Chemtech Trading W.L.L | Industrial Manufacturing |
| chill service trading and contracting qatar | Conglomerates |
| Chillservice Trading & Contracting | Industrial Manufacturing |
| Chip Qatar Solution Trading & Contracting WLL | Information Technology |
| Chiyoda Almana Engineering LLC | Construction |
| CICO Consulting Engineers | Construction |
| Circle Qatar Ltd | Services |
| City Center Doha | Real Estate |
| City Elevators & Escalators Co.W.L.L | Construction |
