| OPU | No. of Staff |
| ASEAN Bintulu Fertilizer Sdn Bhd | 4 |
| KLCC Projeks Services Sdn Bhd | 1 |
| KLCC Property Holdings | 1 |
| KLCC Urusharta Sdn Bhd | 1 |
| Malaysian Refining Company Sdn Bhd | 33 |
| Malaysia LNG Sdn Bhd | 55 |
| PETRONAS Chemicals Ammonia Sdn Bhd | 2 |
| PETRONAS Chemicals Derivatives Sdn Bhd | 4 |
| PETRONAS Chemicals Ethylene Sdn Bhd | 3 |
| PETRONAS Chemicals Fertiliser Kedah Sdn Bhd | 4 |
| PETRONAS Chemicals Marketing (Labuan) Ltd | 10 |
| PETRONAS Chemicals Methanol Sdn Bhd | 2 |
| Pengerang Chemicals MTBE Sdn Bhd | 17 |
| PETRONAS Chemicals Polyethylene Sdn Bhd | 1 |
| Pengerang Power Sdn Bhd | 1 |
| Pengerang Refining Company Sdn Bhd | 14 |
| PETRONAS Chemicals Group Berhad | 9 |
| PETRONAS Refinery and Petrochemical Corporation Sdn Bhd | 35 |
| PETRONAS Chemicals Fertiliser Sabah Sdn Bhd | 1 |
| PETRONAS Energy & Gas Trading Sdn Bhd | 1 |
| PETCO Trading Labuan Company Ltd | 5 |
| Petroliam Nasional Berhad | 289 |
| PETRONAS Carigali Sdn Bhd | 182 |
| PETRONAS Chemicals LDPE Sdn Bhd | 4 |
| PETRONAS Dagangan Berhad | 26 |
| PETRONAS Floating LNG (Satu) Ltd | 5 |
| PETRONAS Gas Berhad | 28 |
| PETRONAS ICT Sdn Bhd | 28 |
| PETRONAS LNG Ltd | 6 |
| PETRONAS Lubricants Marketing (Malaysia) Sdn Bhd | 1 |
| PETRONAS Management Training Sdn Bhd | 9 |
| PETRONAS Penapisan (Terengganu) Sdn Bhd | 38 |
| PETRONAS Research Sdn Bhd | 2 |
| PETRONAS Technical Services Sdn Bhd | 17 |
| PETRONAS Technical Training Sdn Bhd | 9 |
| Petrosains Sdn Bhd | 5 |
| PRPC Utilities and Facilities Sdn Bhd | 1 |
| Universiti Teknologi PETRONAS | 398
|
