Abstract: [Purpose/Significance] At present, there is relatively little research on the open science (OS) policy at the level of scientific research institutions in China, while some preliminary explorations have been made abroad. The text analysis of OS policies of representative scientific research institutions and lessons drawn from their policy making experience can provide a good reference for the formulation of OS policies by Chinese scientific research institutions. It gives play to the main role of scientific research institutions in the OS process, and promotes the practice of OS from bottom to top. [Method/Process] Based on the perspective of policy tools, this paper uses the content analysis method to conduct quantitative analysis on 12 OS policy texts published by international scientific research institutions. It establishes an X-Y two-dimensional analysis framework for OS policy of scientific research institutions. The content analysis categories are as follows: policy instrument dimension (X dimension) - authority, incentive, symbol and exhortation, capacity building, and system change; OS content factor dimension (Y dimension) - open content, open process, open infrastructure, and open cooperation. This paper carries out research through the X-Y two-dimensional analysis framework, aiming to reveal the use of policy tool preferences and policy content focus on the tendency, refining the key factors of research institutions' OS policy, putting forward the policy tool optimization strategy and providing insights into Chinese scientific research institutions in formulating OS policies. [Results/Conclusions] From the dimension of policy tools, capacity building tools are more used, followed by authority tools, and other policy tools are less used. From the dimension of OS content elements, the eight themes of open data, open access, OS education and training, open cooperation, open evaluation, open infrastructure, open incentive and citizen science are the main concerns in the OS policies issued by international research institutions. The use of OS policy tools in scientific research institutions should coordinate with each other, optimize the combination of policy tools; try to solve the actual problems, strengthen the internal balance of policy tools; adjust measures to local conditions and make full use of differences in policy tools. In formulating OS policies, scientific research institutions should further integrate themselves into the international OS tide, understand the development trend, and ensure the forward-looking of policies; adjust and optimize the organizational structure, clarify the division of responsibilities, and promote open scientific practice in an overall way; the core elements and key issues of OS policies should be grasped when formulating policies; and in the process of policy formulation and implementation, they should ensure the investment of funds, as well as timely dynamic adjustment.

Key words: open science (OS), open science policy, scientific research institution, policy tools