This paper examines the extent to which innovative Spanish firms pursue improvements in energy efficiency (EE) within their innovation objectives. The increase in energy consumption and its impact on greenhouse gas emissions justifies the greater attention being paid to energy efficiency and especially to industrial EE. The ability of manufacturing companies to innovate and improve their EE has a substantial influence on reaching the objectives regarding climate change mitigation. Despite the effort to design more efficient energy policies, the EE determinants in manufacturing firms have been little studied in the empirical literature. From an exhaustive sample of Spanish manufacturing firms and using a probit model, we examine the energy efficiency determinants to those firms that have innovated. To carry out the econometric analysis, we use a panel data coming from CIS (Community Innovation Survey) for the period 2008-2011 that includes 4,458 manufacturing firms. Among firm characteristics, the empirical results underline the importance of size in facilitating the adoption of technology that improves energy efficiency; while among the factors related to companies’ behavior, the favorable influence of organizational innovations and innovations related with the reduction of environmental impacts stand out as the main factors in carrying out innovations with the objective of increasing energy efficiency.