Hiroko Inoue studied cultural anthropology at university. In 1974, her fieldwork took her to Okinawa, where she studied the production process of Ryukyu indigo, which differs from island to island. She stayed there for two years to study dyeing and weaving. Based on this experience, she began working in 1992 as a colourful fibrework artist. However, the Kobe Earthquake of 1995 marked a turning point, and her style shifted to place the social perspective at the core of her work.

In 1998, H. Inoue received a special award from the city of Düsseldorf and the Goethe Institut Osaka Kyotoat the Osaka Triennale. As an extra component of the award, in 1999 she was given a studio in Düsseldorf, where she held a solo exhibition. This marked the beginning of a series of activities that led Inoue to shuttle between Germany and Japan.

Since that time, Inoue has created works on the theme of the emotional pain of people living in quarantine and the boundaries that separate people from each other. Early on, she created Absence (1997–2001) – an installation of black-and-white photographs of the interior and windows of a psychiatric hospital, which was exhibited in Tokyo and Germany. Later, as a member of a German video production team, she travelled around the world, including to Alaska and Yemen, before creating an installation of 3/4-length portraits of adolescents standing with their eyes closed, titled What Wilt Thou (2003), which was shown in Tokyo, Nagoya and Mulheim. H. Inoue had previously taken photographs of rooms in quarantine facilities without including human figures, making her first portraits of humans when she visited remote areas around the world to take photos. This stemmed from the realisation that she wished to document how children are victims of conflicts and domestic violence in various regions around the world.
In 2005, H. Inoue was tasked by the Agency for Cultural Affairs to document histories of cultural exchange, and stayed in Vienna for a year to work on the project. This resulted in the 2005 solo exhibition Inside-Out at the Jugendstiltheater in the Otto Wagner Psychiatric Hospital in Vienna, featuring an installation of colour photographs of high school students around the world standing with their eyes closed, as well as photographs of windows. The work was highly acclaimed and was acquired by the Wien Museum MUSA, while the series was subsequently exhibited in Germany and Japan. In addition, Inoue published a book also titled Inside-Out (2009) of colour photographs of rooms and windows in psychiatric hospitals in Japan and Vienna, juvenile prisons and sanatoriums in Germany, and the ruins of Nazi concentration camps, taken at the various institutions she visited.

Following the Great East Japan Earthquake of 2011, H. Inoue created the installation Mori (2011-2012), consisting of photographs of forests in Germany and Japan. This was shown in a solo exhibition in Dortmund, and in the exhibition “Women In-Between: Asian Women Artists 1984-2012”, which travelled to four museums in Japan. The forests photographed by H. Inoue for this exhibition were the artificial forests near the abandoned coal mines in the Ruhr region of Germany, as well as the forests of the Reichswald, which had been the site of fierce battles during World War II. In Japan, H. Inoue photographed the ancient forests of Nara – where she now lives, and which date back to the time of the creation myths of Japan – as well as the pine trees on the Sanriku Coast, an area hit by the Great East Japan Earthquake. In other words, each landscape has its own story and history, and viewers are encouraged to revive the historical memories behind these landscapes. Mori was later acquired by the MAK – Museum of Applied Arts in Vienna.

In 2014, H. Inoue began working on the theme of water as the source of life. She presented the results in 2016 as the black-and-white photographic series MIZU (2016-2024). These works, taken at a thermal power plant in the Ruhr region of Germany, depict a silvery ‘rain’ — a shower of water used for cooling that contains toxic substances, water that is the opposite of the natural rain that nurtures life. This cooling water crashing down like a torrential downpour was also filmed and exhibited alongside the photos. From 2023-24, Inoue visited refugee camps in Berlin, interacting with refugee women from Ukraine and the Middle East and taking their portraits. This new works, Being in the face, were immediately acquired and exhibited at the StadtmuseumDüsseldorf.