Improving the knowledge management (KM) capability in order to gain sustainable competitive advantages has emerged as an important strategy for addressing recurring problems in a new product development such a long time-to-market, riskiness and high development costs. Synthesizing prior theoretical research in innovation management, competitive advantages, KM and practical activities of high-technology engineering enterprises it is posited that innovation, engineering processes and organizational culture are important antecedents of KM capability. However, it is vague whether the KM capability as a mediator affects competitive advantages. The aim of the paper is to explore the impact of the KM capability in hightechnology engineering enterprises. To achieve this aim we have contributed an empiric research in which 50 high-technology engineering enterprises of Russia were involved. The regression analysis is applied to analyze the obtained empiric data. Among the three selected antecedents the engineering processes have the most impact on the KM capability. The research hasn't proved the mediating role between the KM capability and competitive advantages because of relative novelty of this phenomenon to Russian hightechnology enterprises.