The National Heritage Memorial Fund award will go towards securing the Fox Talbot Archive - the only significant collection related to "the father of photography" remaining in private hands.
New York photographs dealer Hans P Kraus Jr is selling the archive on behalf of the Talbot family. He said: "The archive contains significant information for future Talbot research. It is a core archive of the 19th century, containing original documents, artworks and artefacts which reflect the personality and wide-ranging achievements of the brilliant man primarily known as the inventor of photography on paper."
The Bodleian already has a copy of The Pencil of Nature, Talbot's ground-breaking 1844 book that was the first commercial publication to be illustrated with photographs. "The archive that we hope to buy contains several of the very objects photographed by Talbot for the book," said a spokeswoman.
"We have extensive existing photographic holdings, some of which are extremely important (e.g. the Julia Margaret Cameron album), and all of which deserve far greater attention. Photography is a growing academic discipline within the university. Oxford has attracted very significant photographic resources over the past 175 years.
"The Bodleian's holdings begin with the tens of thousands of books published in the 19th and 20th century that were illustrated with original photographs or photomechanical images, from The Pencil of Nature onwards."
If the Bodleian buys the archive - which has an export licence - it will open an exhibition in 2017.
It includes the first photograph believed to have been taken by a woman (his wife, Constance) and estate records from Lacock Abbey, his Wiltshire home, now run by the National Trust.