In 1935 he wrote music and lyrics of "O mia bela Madonina" ("My beautiful little Madonna"), a song dedicated to his hometown which soon became very popular and a sort of unofficial city anthem.

Between the 1930s and 1950s Giovanni D'Anzi and Alfredo Bracchi formed a very prolific pair of songwriters.

Most of their songs were in Milanese dialect, and described ironically characters of the past in Milan, for example "La gagarella del Biffi Scala" (the spoiled daughter of Mr Biffi Scala) and "El Tumiami de Luret" (the braggart from piazzale Loreto), El Biscella (the silly-bully boy).

Milan's local authorities included him in the list of important Milanese people at the Monumental Cemetery in the Civico Mausoleo Palanti.

In 1990 to his memory a plaque was hung in Galleria del Corso in Milan, in front of the place where he worked and near where he lived, the plaque reads "once upon a time in this gallery there was a king: Giovanni D'anzi, he wrote magic notes, and the sweetest serenade he sang for Milan : Oh mia bela Madonina " In his memory, since 1995, the Gruppo Editoriale Curci under the auspices of the Comune di Milano and the association " Amici della musica e dello spettacolo " organizes the annual Award Giovanni D'Anzi, singing event in Milanese dialect.