IJN & USN subs went looking for ships to sink.
Five midget submarines participated in the attack.
Short answer: The Japanese attacked with airplanes from six aircraft carriers, and they also used submarines. The standard-sized submarines were in the Hawaiian waters outside of Pearl Harbor, and midget submarines were sent into Pearl Harbor itself. Details on the web.
The midget subs did no actual damage
Japanese pilots from the Zuikaku and Shōkaku aircraft carriers are the pilots who bombed Pearl Harbor. There were also six mini submarines that were sent to attack the ships but they were not very successful.
Submarines and aircraft carriers
Submarines and Aircraft Carriers
The Japanese used mini-submarines. Very small submarines housing only a few men. The attack on Pearl Harbor itself was mostly an air raid. There were five mini subs that launched in total. It is believed that only two actually entered the harbor and that only one released a torpedo.
Only Japan's Naval submarines and airplanes attacked the base.
Submarines and aircraft carriers
Submarines and aircraft carriers
There were no submarines sunk or damaged during the attack on Pearl Harbor; all vessels either sunk or damaged were capital ships (battleships, cruisers, etc.) or support vessels (tenders, tugs, etc.).
See website: Pearl Harbor Attack