Yoshizawa has short dark-colored hair and a goatee.
In the movie Yoshizawa plays a very minor role, merely a lackey of Matoba's, providing brute force when necessary.
In the novel, however, Yoshizawa is more significant. He is sub-leader of the Blue Ship organization, ranked below only Daisuke Matoba.
Yoshizawa is first seen when the Nikaido Research Lab is infiltrated. When Maki Nikaido makes her escape, Yoshizawa and her other pursuers run after her up the stairs, but Maki throws down several fire extinguishers, hitting Yoshizawa, along with several others; Yoshizawa was unfortunate enough to get one to the face.
Maki feels to a vault in her father’s office, and Yoshizawa is instructed to open it. With a laptop and two alligator clips, Yoshizawa manages to hack the lock and its programming in only a few minutes. He opens the safe door, only to find that she had escaped through a trap door.
Matoba, who remains rather calm, questions who Nikaido would have given the data they require to, guessing that he would give it to the person he trusts the most. Yoshizawa suggests that his daughter would have it. Knowing that it would be difficult finding her, Yoshizawa suggests releasing the virus without the antidote, though Matoba colds him, saying that he won't allow him to jeopardize the plan or to degrade their goal to an act of terrorism.
After Blue Ship gains possession of the Death Note, Yoshizawa reads off the rules. In order to test out the 13-day rule, he suggests that Konishi test it out on someone he wants dead.
When Kujo is undercover at the Pandemic Task Force, she contacts Yoshizawa to fill him in on important information regarding leads on Maki and L. At one point, Kujo informs Yoshizawa of a possible lead, but it ends up being an unwitting decoy.
Yoshizawa later uses Blue Ship member Konishi’s planted bug in order to reverse eavesdrop and find out about Maki and Kujo’s meeting. He and the others go and retrieve both Maki and what Kujo claims is the antidote.
When Maki is held captive, L and Suruga meet Hatsune and Yoshizawa in a building, demanding the Death Note. L hands over the Death Note, and, to see if it is real, L is told to write his name down. L does so, and jumps off of the building; Hatsune and Yoshizawa look over the edge of the building and see a body on the ground (which is actually Matsuda, who disguised himself as L as part of a L's plan). Now convinced that the Death Note is real, they demand that Suruga write his name down, and after much pleading, Hatsune and Yoshizawa allow Suruga to write down that he will die an hour later, but not touch any of the equipment.
When on the plane to Los Angeles, things go amiss when Matoba notices that Maki is beginning to exhibit symptoms of the virus. Once it is revealed that Kujo has other plans, ones that involve killing Matoba and everyone on the ship, she, Konishi, and Robert Fairman hijack the plane. As Kujo explains her motives to Matoba and the others, revealing that she had secretly injected them all with the virus. Matoba notices that Kujo is crying tears of blood: a symptom of the virus. Matoba falls to the ground, screaming that he does not want to die.
Hatsune leaves, disgusted with his humiliating display, and Yoshizawa then proceeds to scold Konishi. Konishi has a gun pointed at Yoshizawa, yelling at him and accusing him of never planning on letting him live in the new world. Konishi yells in outrage about how Yoshizawa always mocked him and called him names, and that he deserves to die. Yoshizawa, realizing that he had pushed Konishi off the edge, apologizes profusely, begging Konishi not to shoot. However, Konishi does not heed his request, and shoots Yoshizawa three times, killing him.