| Basic Characteristics | Properties (Haemophilus parainfluenzae) |
| Capsule | Variable |
| Catalase | Variable |
| Gas | Variable |
| Gram Staining | Gram-negative (-ve) |
| H2S | Positive (+ve) |
| Hemolysis | Negative (-ve) |
| Indole | Variable |
| Motility | Negative (-ve) |
| Nitrate Reduction | Positive (+ve) |
| Nitrite Reduction | Positive (+ve) |
| Oxidase | Positive (+ve) |
| Shape | Small, pleomorphic rods, usually with long, filamentous forms. |
| Urease | Variable |
| V-factor requirement | Positive (+ve) |
| Adonitol | Negative (-ve) |
| Arabinose | Negative (-ve) |
| Cellobiose | Negative (-ve) |
| Dulcitol | Negative (-ve) |
| Erythritol | Negative (-ve) |
| Fructose | Positive (+ve) |
| Galactose | Positive (+ve) |
| Glucose | Positive (+ve) |
| Glycerol | Variable |
| Inositol | Negative (-ve) |
| Inulin | Negative (-ve) |
| Lactose | Negative (-ve) |
| Maltose | Positive (+ve) |
| Mannitol | Negative (-ve) |
| Mannose | Positive (+ve) |
| Melibiose | Negative (-ve) |
| Raffinose | Variable |
| Rhamnose | Negative (-ve) |
| Salicin | Negative (-ve) |
| Sorbitol | Negative (-ve) |
| Sorbose | Negative (-ve) |
| Sucrose | Positive (+ve) |
| Trehalose | Negative (-ve) |
| Xylose | Negative (-ve) |
| Alkaline Phosphatase | Positive (+ve) |
| Arginine Dihydrolase | Negative (-ve) |
| Esculin Hydrolysis | Negative (-ve) |
| Fucosidase | Negative (-ve) |
| IgA1 protease | Negative (-ve) |
| Lysine decarboxylase | Variable |
| ONPG (β-galactosidase) | Variable |
| Ornithine Decarboxylase | Variable |