Christian Franzen Nissen (1864–1923) was a Danish photographer and diplomat largely active in Spain.

Specialised in portrait photography and often employed by the Spanish royal family, he reportedly self-styled as "Photographer of Kings and King of Photographers".

[2] Once settled in Spain, he opened a photographic studio at the Madrid's calle del Príncipe [es].

[2] Very appreciated by Queen Mother Maria Christina, he was able to take many full-body portraits of the Spanish royal family and the aristocracy.

[3] He was, along with Kaulak, one of the best known portrait photographers in Spain by the turn of the 20th century.