The article presents a review of approaches to assessing the business climate for innovation. Composite indexes are considered the main tool for comprehensive monitoring of a wide range of external environment factors that determine the favorability of the business climate for innovation. The paper discusses the opportunities and limitations of analyzing the innovation climate using international rankings; and formulates the main requirements for such projects for targeted use to analyze national innovation systems and improve state regulation of innovation. The paper identifies and analyzes 16 international projects that indirectly or directly provide an aggregated country-level assessment of the conditions and (or) results of innovation activities. It is shown that the approaches of indexes developers to determine the innovation climate often have no theoretical justification, and only some of the projects are characterized by publicly verifiable methodology, sustainability of assessments and transparency of initial data. The Global Innovation Index, which satisfies most of the formulated criteria, stands out in this row. Based on the Global Innovation Index example, the empirical part of the article uses its longitudinal data for 2017-2021 to identify strengths and weaknesses of the national innovation system of Russia, taking into account benchmarking of development dynamics across a wide range of countries covered by the harmonized observation. The obtained results reflect the analytical potential of international innovation rankings, as well as allow identifying factors which may contribute to or hinder the achievement of the global innovation leadership and formulating policy recommendations.