The officer was shot in a busy area, by two gunmen riding a motorbike. The assailants had intercepted Captain Nadeem's vehicle and opened fire, killing him on the spot, a local police official said.
While Nadeem died on the spot, his wife sustained a bullet injury in the attack and was rushed to the Naval hospital.
Nadeem taught at the Karachi campus of the National University of Sciences and Technology.
Ealier in February, a lieutenant commander of the Pakistan Navy who was wounded in an attack, succumbed to injuries. In another incident in the same month, a naval officer and his wife were injured in an explosion while they were in their car.
Karachi, Pakistan's largest city is suffering from an unprecedent wave of killings that is blamed on militants, criminals, and political tensions.
However in Nadeem's case no one has claimed the responsibility for the attack.
According to the Human Rights Commission of Pakistan, In the first six months of 2013, 1,726 people were killed compared with a previous high of 1,215 in the same period last year.