The novel is told in the voice of Ono, who is an unreliable and ambiguous narrator. He sometimes seems to regret his past actions, but also obliquely stresses his pre-war values, the admiration he received from others, his considerable technique as a painter.
The novel also describes Ono's family, his daughters Setsuko who is already married and Noriko who is looking for a partner. There are decidedly overtimes of Ozu's films here. Ono also regrets Japan's American occupation and rapid Westernization, and his children's easy acceptance of those two.
The world is rapidly changing all the time (a "floating world"), what is man's role in such a world? Just as Ono was more a hack painter than a genuine artist, so as a human being he seems to have floated on the stream, without making any moral choices. And also now, although he has all the tools to judge his life at his disposal, he again floats on, closing his eyes to reality.
I read An Artist of the Floating World as a Faber and Faber paperback.