The development of informed views of nature of science is considered to be a crucial aim for science education. This study assesses Portuguese prospective science teachers’ views of the nature of science before and after an intervention programme that took place in the first year of their master. Nine prospective science teachers that will teach biology and geology in middle and high schools voluntarily participated in this study. Pre and post questionnaires, interviews and lesson plans were analysed. Results show that prospective science teachers improved their views of nature of science. However, some of them still struggled with some aspects, which stresses the need for a better understanding of the factors that influence science teachers’ views of nature of science. Despite the positive results, more research is needed to understand the factors that mediate teachers’ views into their instructional practice, namely by observing and monitoring teachers’ practices and work environment.