| Henry, Count of Nassau-Siegen | |
|---|---|
| Born | c. 1288 |
| Died | 1 August 1343 (aged 54–55) |
| Noble family | House of Nassau |
| Spouse(s) | Adelheid of Heinsberg |
| Father | Otto I of Nassau |
| Mother | Agnes of Leiningen |
Henry, Count of Nassau (Dutch: Hendrik van Nassau-Siegen, German: Heinrich III. von Nassau) (before 1288 – July/August 1343) Count of Nassau-Siegen, of Grimborg, Heiger, Westerwald, later of Molsberg, and after his brother's death of Dillenburg. He was a son of Count Otto I of Nassau and Agnes of Leiningen.
Henry married Adelheid of Heinsberg, daughter of Dirk of Heinsberg and Blankenberg and Johanna of Leuven. They had five children: