Yes - If we define a 'solar system' as a star ('sun') with its associated planets and other objects in orbit around it. The Milky Way (our galaxy) consists of thousands of millions of stars - of all sizes, temperatures, colours etc. For some years now astronomers have been observing some of these stars, and by various techniques (using delicate and sensitive measurements) they have now discovered hundreds of planets orbiting many of the these stars. Most of these were like Jupiter - large gas giants - but this type of planet would be much more likely to be discovered because of its size and mass. However, more recently smaller planets - more earth like - have been discovered too. So, many solar systems have been discovered in the Milky Way. If we reaise that, like our own galaxy, the Milky Way, there are thousands of millions of whole galazies out there each with thousands of millions of stars - so the possibilities of them having their own systems is very very high. Astronomers now believe that solar systems are the norm rather than a rarity.