- Heinz-body anemia, congenital 282.7
- Heller's disease or syndrome (infantile psychosis) (see also Psychosis, childhood) 299.1
- Helminthiasis (see also Infestation, by specific parasite) 128.9
- Heloma 700
- Hemangioblastoma (M9161/1) - see also Neoplasm, connective tissue, uncertain behavior
- Hemangioblastomatosis, cerebelloretinal 759.6
- Hemangioendothelioma (M9130/1) - see also Neoplasm, by site, uncertain behavior
- Hemangioendotheliosarcoma (M9130/3) - see Neoplasm, connective tissue, malignant
- Hemangiofibroma (M9160/0) - see Neoplasm, by site, benign
- Hemangiolipoma (M8861/0) - see Lipoma
- Hemangioma (M9120/0) 228.00
- Hemangiomatosis (systemic) 757.32
- Hemangiopericytoma (M9150/1) - see also Neoplasm, connective tissue, uncertain behavior
- Hemangiosarcoma (M9120/3) - see Neoplasm, connective tissue, malignant
- Hemarthrosis (nontraumatic) 719.10
- Hematemesis 578.0
- Hematidrosis 705.89
- Hematinuria (see also Hemoglobinuria) 791.2
- Hematite miners' lung 503
- Hematobilia 576.8
- Hematocele (congenital) (diffuse) (idiopathic) 608.83
- Hematocephalus 742.4