Exhibit 21
List of Subsidiaries of Olympic Steel, Inc.
| Name of Subsidiary | State of Organization | % Ownership |
| Olympic Steel Lafayette, Inc | Ohio | 100% |
| Olympic Steel Minneapolis, Inc. | Minnesota | 100% |
| Olympic Steel Iowa, Inc. | Iowa | 100% (a) |
| Oly Steel NC, Inc. | Delaware | 100% |
| Tinsley Group – PS&W, Inc. | North Carolina | 100% (b) |
| IS Acquisition, Inc. | Ohio | 100% |
| Olympic Steel Trading, Inc. | Ohio | 100% |
| Chicago Tube and Iron Company | Delaware | 100% |
| Metales De Olympic, S. de R. L. de C.V | Mexico | 100% (c) |
| B Metals, Inc. | Ohio | 100% |
| MCI, Inc. | Ohio | 100% |
| ACT Acquisition, Inc. | Texas | 100% |
| (a) Owned 100% by Olympic Steel Minneapolis, Inc. | ||
| (b) Owned 100% by Oly Steel NC, Inc. | ||
| (c) Owned 100% by Olympic Steel Trading, Inc. |