In 2015, the World Health Organisation rated toxoplasmosis as one of the most important food borne zoonotic diseases in the world. In addition, recent studies have associated Toxoplasma gondii sero-positivity with severe mental illnesses such as schizophrenia. Intake of raw or insufficiently cooked meat has been suggested to pose a major risk of T. gondii transmission in Europe. The objective of this study was to assess the T. gondii sero-prevalence in Danish pigs divided into sub populations (sows versus finishers, indoor versus outdoor). Serum samples were collected from 89 indoor-reared sows, 128 indoor finishers and 37 outdoor-reared finishers and analysed using an antibody ELISA with a sensitivity of 76.3% and a specificity of 93.7%. It was found that 33.7% indoor-reared sows, 3.1% indoor-reared finishers and 10.8% outdoor reared finishers were T. gondii sero-positive. The sero-positivity of T. gondii was significantly higher for indoor-reared sows compared to indoor-reared finishers (RR = 10.9, (P < 0.001). Although, the probability of T. gondii sero-positivity for outdoor-reared finishers was 3.5 times higher than for indoor-reared finishers, the difference was not statistically significant (P = 0.14). The next step will be to identify specific risk factors for sero-positivity for indoor and outdoor production as well as for finishers and sows, and to use this information to help swine producers to prevent infection in their pigs.