Games-based Learning (GBL) has developed a reputation with educationalists it is perceived as a potentially engaging form of supplementary learning that could enhance the educational process and has been used at all levels of education including primary, secondary and tertiary education. Despite this recognition and utilisation there is still a lack of empirical evidence supporting GBL as an approach. This paper presents the findings of a systematic literature review performed from 2000 to 2013 specifically looking at quality empirical studies associated with the application of GBL in Primary Education (PE) categorising studies into: behavioural change, affective and motivational outcomes, perceptual and cognitive skills and knowledge acquisition and content understanding. This paper presents a synthesis of these high quality studies associated with GBL. The studies showed that GBL have been used to teach a variety of subjects to children and young people in PE with mathematics, science, language and social studies being the most popular.