Private Lazzaro Portinari was a soldier of the British Army who died during the First World War.

He was born in Italy, the son of Marcello and Maria Portinari. With his family, Portinari settled in London, where his father was employed as a cook. At the time of the 1911 census, Portinari was working as a restaurant waiter and living with his family at 10 Wells Buildings.

Portinari died on 29 September 1918, during the Allied Hundred Days Offensive, while serving with the 2/4th Battalion, The Duke of Wellington's (West Riding Regiment) on the Western Front..He formerly belonged to the East Yorkshire Regiment.  His brother, Francesco, a sapper in the Royal Engineers, died two months later, on 5 November, in England.

He is buried in Masnieres British Cemetery, Marcoing, in Nord, France.