Macleans College has contacts with Germany, Thailand, Korea, China, Malaysia and Hong Kong.

The school was opened in 1980 by the Governor General, Sir David Beattie, with a roll of 199 students. The school is co-educational and was the first S80 or whanau house school built in New Zealand. It now has a roll of over 2200 students. Each whanau house comprises a large building with a variety of teaching spaces and a commons area which acts as a social space. The whanau is an extended family of approximately 280-300 students which operates as a mini school within the larger school. On arrival at Macleans College a student is placed in a form class. The form class is assigned to one of the whanau houses. The students remain in that form class and, therefore, in that house for the duration of their time at the college.

The school is named after the Maclean family who immigrated to New Zealand in 1850 and farmed the area on which the school is built. The family has its origins in Scotland. They left in 1745 following the Jacobite rebellion to take refuge in Cornwall. Here they lived near the small village of Blisland, close to Bodmin. While in Cornwall they were known by the name 'Lean', but in 1845 the surname Maclean was resumed by some of the family. Originally two brothers, Robert and Every Maclean, together with Robert's wife, Mary, and daughter, Ellen, migrated to Auckland. They were followed later by a younger brother, Benjamin, who was a tutor at St John's College. Their elder brother, John, remained in Cornwall. Robert and Every successfully developed the farm at 'Bleak House' and were well known citizens of the district. Every, in particular, was a prominent figure in public affairs and a founder of the Auckland Agricultural Company. Mrs Maclean was known as a woman of exceptional character and energy who skillfully ran the farmhouse and tended to the sick in the area with her own home made remedies. She died in 1891, Every in 1901, and Robert, to whom there is a memorial stained glass window in All Saints Church, Howick, in 1888.

The official emblem of the school, worn on the students' jerseys, incorporates as a centrepiece a castle from the Maclean family crest, and is set against six waves. The waves also symbolise the physical setting of the school. The emblem represents the Macleans philosophy of basing school values on the best of the old and the new.