Alexander Lean (21 May 1824 – 20 November 1893) was a New Zealand runholder, architect, military volunteer and musician. He was born in London, England on 21 May 1824.^[1] His most valuable contribution as an architect were the Christchurch Supreme Court buildings,^[1] which were progressively demolished between 1974 and 1985.^[2]

In 1853, Lean was the original purchaser of land at the bottom of Rāpaki Track next to the Ōpāwaho / Heathcote River, which he called Riverlaw. He sold this land in 1859 to Michael le Fleming and with an additional intermittent owner, the property was purchased by Hugh Murray-Aynsley in 1862.^[3]

Lean acted as the returning officer for the Christchurch electorate in the 1893 election when he suddenly died on 20 November 1893 in Christchurch.^[4][5] He is buried at St Peter's in Upper Riccarton.