The thesis focuses on potential use of social networks in supporting innovation activities within companies. The main objective of the paper is to clarify the relationship between innovation activities in companies and its possible support by social network followed by presentation of suitable social networks which allows developing contacts, communication, sharing and cooperation in innovative activities. The objective is fulfilled by defining social networks and innovation; analysing related innovation activities of companies and its possible support through social networks; introducing appropriate social networks; evaluating innovative environment for business and examining awareness and applicability of these innovative concepts: open innovation, innovation marketplaces and collaboration platforms in Czech companies. The main contribution of the thesis is defining social networks in relation to innovation activities of companies, that gives the reader insight into the topic of social networks and innovation; designing an assessment framework of social networks that support innovation and creating an overview of existing social networks that enables innovation activities, which should help companies in easier orientation within services and functionality that analyzed web portals offer. The theoretical part of this paper defines the terms of social networks and innovation, and then explains the relationship of social networks and innovative activities. The theoretical part is followed by an overview of existing social networks that can be used as a support for innovation. The paper then focuses on the innovation environment in the Czech Republic in comparison to Sweden. The last chapter examines the awareness and applicability of social networks in supporting innovation activities in Czech companies.