Exhibit 21
SUBSIDIARIES OF SOLUNA HOLDINGS, INC.
| Subsidiary Name | Jurisdiction of Incorporation or Organization | |
| Soluna Callisto Holdings, Inc. | Delaware | |
| Soluna Digital, Inc. | Nevada | |
| Soluna Global Services, Inc. | Nevada | |
| Soluna Cloud, Inc. | Nevada | |
| Soluna Energy, Inc. | Nevada |
SUBSIDIARIES OF SOLUNA DIGITAL, INC.
| Subsidiary Name | Jurisdiction of Incorporation or Organization | |
| Soluna MC, LLC | Nevada | |
| Soluna SW Holdings, LLC | Delaware | |
| Soluna DV Devco, LLC | Nevada | |
| Soluna DV ComputeCo, LLC | Delaware | |
| Soluna DV Services, LLC | Nevada | |
| SDI SL Borrowing - 1, LLC | Nevada | |
| Soluna DVSL II ComputeCo, LLC | Delaware | |
| Soluna KK I ComputeCo, LLC | Nevada |
SUBSIDIARIES OF SOLUNA SW HOLDINGS, LLC
| Subsidiary Name | Jurisdiction of Incorporation or Organization | |
| Soluna SW, LLC | Delaware |
SUBSIDIARIES OF SOLUNA MC, LLC
| Subsidiary Name | Jurisdiction of Incorporation or Organization | |
| Soluna MC Borrowings, LLC 2021-1 | Delaware |
SUBSIDIARIES OF DV DEVCO, LLC
| Subsidiary Name | Jurisdiction of Incorporation or Organization | |
| Soluna DVSL ComputeCo, LLC | Delaware |
SUBSIDIARIES OF SOLUNA ENERGY, INC.
| Subsidiary Name | Jurisdiction of Incorporation or Organization | |
| Soluna KK Energy ServiceCo, LLC | Nevada |
SUBSIDIARIES OF GLOBAL SERVICES, INC.
| Subsidiary Name | Jurisdiction of Incorporation or Organization | |
| Soluna EPC Services, LLC | Nevada | |
| Soluna US Services, LLC | Nevada | |
| Soluna EPC Services II , LLC | Nevada |
SUBSIDIARIES OF SOLUNA CLOUD, INC.
| Subsidiary Name | Jurisdiction of Incorporation or Organization | |
| Soluna AL CloudCo, LLC | Delaware |