Yeah they do, I got basically the same one but a bit cheaper. And mostly fruitflies were caught as well as regular flies and Mosquitoes. I can show you the picture, but I can't unfortunately because I did not bought this exact one. But if mine which is basically the same but cheaper, this one will do it too for sure. Just make sure it's one of the only lights in the room, so they come to the light. Also a lifehack is placing not too narrow glass of a little bit of red wine. Idk what to put over it or something, but my dad makes it work, something weird about the flies is that they become drunk basically. Perfect for placing it on a high place. This is only done when it's still light outside in our house. Be aware of the shock sounds of the flies tho 🤣. I was sleeping and thought my electricity was going to get out, but don't worry about that tho lol. But to answer shortly, yes, almost all flies fly to the light. For me it was just crazy how much flies get caught in it when it's almost dark. But idk what kind of flies u are trying to get rid of exactly. Sorry for the inconvenience of reading all this but it doesn't work on bigger flies like wasps or something. Good luck tho, if I already got it, I would like to know if I was wrong. Sincerely, Fredo Sultana