In the last decades a large body of literature has examined the role of domain-general and domain-specific precursors of mathematical learning disability and some studies confirmed that some abilities of kindergartners can predict later mathematical achievement outcome (Mazzocco & Thompson, 2005; Passolunghi & Lanfranchi, 2012; Krajewski & Schneider, 2009; De Smedt et al., 2009). The present study examines the possibility to enhance working memory abilities of kindergartners using a specific working memory training and to verify if the memory gain leads to a enhancement of pre-mathematical knowledge. The treatment used focuses on activities designed to enhancement of working memory abilities with special attention to metacognitive and motivational aspects. The results showed a significant treatment effect: the working memory training used, brought to improvements in outcome tasks measuring working memory and mathematical abilities. In particular, there was a significant treatment effect for all active working memory tasks that involve both storage and manipulation of information.