-In the modern economic environment, the innovative-investment activity of companies is acquiring great importance. According to the authors, public-private partnership (PPP) is described as the foundation of the innovative activity, as an essential tool for increasing the efficiency of the national innovative system, which contributes to incentives of investment, and optimal use of material, technical, human and financial resources. The article examines the interaction between the government and private business at different stages of the innovative process which promotes the improvement of design arrangement quality and the efficiency of the investment and innovative activity. In the article, the authors pay special attention to the necessity of application of life cycle contracts (LCC) as an effective instrument of the implementation of public private partnership for the development of the national economy. Also, they give their own definition of "lifecycle contract", and the key characteristics of LCC. The authors suggest a business model of the interaction between the state and private business based on PPP and LCC, contributing to improving the quality of design arrangements and the efficiency of investment and innovative activity in the HPU sector. The advantages and disadvantages of PPP (based on LCC) for the business and government are also identified and substantiated in the article. Moreover, the authors developed and gave scientific and theoretical credence to the technique for efficiency evaluation of investment projects, implemented as part of PPP on the basis of LCC. This technique is based on the use of the net present value, the profitability index, the internal rate of return and take into account possible fluctuations of investment risk. All these factors as a whole enable one to assess the efficiency of investments in innovation-oriented companies. According to the results of the research, the authors concluded that it is the projects of PPP, based on life cycle contracts, that can be the real instruments, contributing to the stabilization and improvement of the situation for the development of innovative-investment activity of the companies.