The title of the poem refers Tithonus, the lover of Aurora in Roman mythology. Tithonus was granted immortality by the gods. However, he continued to age, unable to die.
Tithonus, in the beginning of the poem, laments the cycle of life and death; he considers himself particularly unfortunate as he is doomed to age but not die.
The speaker remembers his youth and becoming immortal. He recounts, also, his aging and his desire to die. Tithonus, then, speaks of Aurora in romantic detail. He states, also, that Aurora now will not speak to him and that she is unable to take back her "gift."
Tithonus reflects on the love he once felt for Aurora and how it has now turned cold. He admires those who are able to die and hopes eventually to be among the dead.