The improvement of protein efficiency (PE) is an essential factor in the development of a sustainable pig production, especially considering its contribution to environmental pollution through nitrogen excretion. In addition, since many countries do not meet the soybean demand of the livestock industry, soybeans are imported from South America, thereby leading to an increased cost of production. It is therefore important to improve proportion of protein retained in the body of pigs. Traits such as feed conversion ratio (FCR) and residual feed intake (RFI) are used to characterize feed efficiency in livestock. However, improving feed efficiency with the aim of reducing nutrient excretion may not be as efficient as selecting on the nutrient trait itself (de Verdal et al., 2011). The aim of this study was therefore to understand the genetic architecture of PE in Swiss Large White pigs by estimating its heritability and its genetic correlations with meat quality traits (such as meat colour, shear force, cooking loss) and production traits (such as average daily gain).