Beginning work as a child actress at the age of three, by the time she became an adult, voice acting had inadvertently become her main occupation.

[8] When she obtained a copy of her family register to apply for high school, she learned that Tsuru was not her biological mother.

[6] Because Tsuru had had a miscarriage and could not give birth, her parents agreed to Ryoshu fathering a child with a woman he knew in order to continue the Nozawa family lineage.

She began voice acting in her late teens, in order to help support the struggling theater company.

[11] Her first regular role was in Uchuu Patrol Hopper (1965),[11] and she went on to voice brothers Tonkichi and Kanta Hanamura in Sally, the Witch (1966).

[3] She went on to voice Tetsurō Hoshino in Galaxy Express 999 (1978), again being selected by the work's original creator Leiji Matsumoto.

[10] However, she noted that this eventually resulted in her landing the role of Son Goku in Dragon Ball (1986), as otherwise she would not have even been allowed to audition.

[10][13] She was chosen to play Goku by Dragon Ball creator Akira Toriyama, who later stated that he would hear Nozawa's voice in his head when writing the original manga.

[16] On August 25, 2004, the Tokyo High Court upheld the ruling against Onkyo Eizo and also found Nippon Animation liable, ordering both companies to pay the 87 million yen.

Planning to make it available in multiple languages, beginning with English and Chinese, the companies acknowledged the potential threat to actors' rights and livelihoods posed by AI, and promised not to use the data for performances in animation or similar works.

[8][26] Although she has sung some songs related to her acting roles, such as the theme to The Monster Kid, Nozawa said she is not a good singer and always tries to get out of it.

This originated in the early days of voice acting when the dubbing of foreign films was done live and actual boys could not be used; staff members would recommend and automatically cast her because they knew she had done it before.

[4] Nozawa also speculated this might be due to her childhood as a tomboy; she was the only girl having sword fights with the boys, and preferred that over playing with dolls.

For Dragon Ball specifically, she said she watches it twice; the first is simply as a fan for personal enjoyment, but the second is to critique her performance and see if there are adjustments that need to be made.

[4] During recording sessions, she avoids speaking with the actors who are playing enemy characters; "Of course, if someone talks to me, I respond, but I try not to initiate conversations myself.

[28] Her colleague Toshio Furukawa stated there is no one else who can do this, and Nozawa revealed that younger actors once asked her to stop because it gives the impression that anyone can.