The building is Grade II* listed: notable features include its chancel arch made from recycled Roman brick.

[2] Some sort of simple wooden church was probably made necessary in 796 when St Albans Abbey took possession of the Manor of Sandridge.

The oldest surviving feature of the present church is possibly the semi-circular head of the arch between the nave and the chancel, although the date of this uncertain.

[3] It was no later than 1119 that the church was consecrated and dedicated to St Leonard by Herbert de Losinga, first Bishop of Norwich (he died in 1119), and that Sandridge became a parish.

The tower collapsed in 1692 or 1693 and the church wardens reported that the rebuilding would cost seven hundred pounds.

In 1786 the rotten walls of the clerestory were removed and the roof lowered and flattened out to rest on the Norman arches.

This structure, which with its flanking walls is a Grade II listed building, was erected after World War I as a memorial.