The objective of this study was to evaluate the effects of roughage on organic growing/finishing pigs’ activity behaviour and social interactions. It was hypothesized that access to additional roughage in the outdoor area would make the pigs use this area more frequently and change their activity pattern and access to the roughage would reduce aggressive behaviour and stress among the pigs. The results confirm that access to additional roughage in the outdoor run did encourage pigs to go outdoors more frequently. This suggests that pigs might be motivated to use the roughage to explore and forage. Although straw was provided indoors, access to additional roughage outdoors affected the pigs to be more active and reduced the aggressive behaviour among them. This indicates that roughage is an important resource that might influence the well-being and the behaviour of pigs.