An insulating-film forming composition comprising: at least one of: a
dendrimer having a core portion and a branched end; and a polymer of the
dendrimer; and a coating solvent, wherein the dendrimer has a cage
silsesquioxane at the core portion, and has a polymerizable group at the
branched end; an insulating film obtained by using the film forming
composition; and an electronic device having the insulating film.