She started modeling as Miyabi for the site shirouto-teien.com in June 2005, which resulted in several sets of photographs and two hardcore gonzo videos. She was then signed by the | S1, an AV company that produces light hardcore pornography, premiering for them on October 7, 2005 with the video New Face. S1 had subsequently released one original video per month until February 2007. She has also participated in several S1 compilation videos including the company’s entry in 2006 AV Open, a competition between Japanese pornographic studios that aims deciding which studio can produce the highest selling video. The video that featured Maria Ozawa, among other AV idols Sora Aoi, Yua Aida, Yuma Asami, and Rin Aoki won the first place. Maria Ozawa and S1 parted ways in early 2007. Along with Rin Suzuka, Reina Matsushima and Rin Aoki, she moved from the safe, but popular S1 to a new startup company, Dasdas (DAS). On April 25, 2007, Dasdas released the first videos of the company, among which is a video featuring Maria Ozawa. Dasdas videos contain scenes of rape, creampie, and physical torture, themes not featured in the light hardcore style of her S1 videos. Besides, she has done V-Cinema films, a photobook and several glamour ("gravure") videos, and appeared in Yokohama hip hop group DS455's music video for the song "Summer Time in the D.S.C.".