This work focuses on analyzing the differences in productivity and the explanatory factors from a microeconomic perspective on a panel data over the period 2000-2010 in 30 Spanish industrial sectors NACE three-digit. The semiparametric methodology it’s proposed to estimate productivity that has allowed to consider the simultaneity of inputs and productivity. The main results show intra-and intersectoral differences in total factor productivity. Regarding the determinants of productivity, size is usually related to higher levels of productivity in parametric methods but in the case of semi-parametric methods this relationship is diverse (U-shape, inverted U-shape, wave-shape). The skills and capital intensity are related positively and negatively respectively.