Land dual values are one of the important aspects of the results of mathematical programming models used to evaluate the impact of agricultural policy measures at regional and farm level. When the decoupling of direct payments and the payment entitlements per hectare are included in PMP models in the context of the Single Payment Scheme (SPS), the analysis of the land dual values is more complex than in models which do not take these aspects into account. In this paper, we present a theoretical analysis of the land dual values when the SPS is included in PMP farm models. This theoretical analysis is carried out for the base year (linear model) and for a simulated year (quadratic model).The results of this analysis are illustrated by comparing numerically the land opportunity costs obtained in the case of partial decoupling and in the case of full decoupling of direct payments.