A video, released by the Ukrainian presidency, shows him inspecting a badly damaged residential building and holding a meeting with local officials.
Mykolaiv, a port and industrial city of almost half a million inhabitants before the war, is still under Ukrainian control, but it is close to the Kherson region, occupied by the Russians. It remains a Moscow target because it lies on the route to Odessa, Ukraine’s largest port, 130 km to the southwest.
The visit comes a day after a Russian strike killed two people and injured 20 in the city.
In the video, local governor Vitaliy Kim shows Mr Zelensky the damage to a residential building. The large building presents a gaping hole, with the interior of the apartments visible.
A blue and yellow Ukrainian trident is visible on one of the broken windows.
Mr. Zelensky also attended a meeting with local officials in what looked like an underground basement, where he handed out awards for bravery.
His office said they had “discussed the state of the economy, the restoration of water supplies and the situation of agriculture.”
“Special attention was paid to land and sea threats. We never stop working for victory,” the statement read.