[目的/意义] 旨在全面了解开放获取论文的数量及开放获取率，并对其质量做出初步评价。[方法/过程] 以Web of Science（WoS）核心合集为数据源，从年代、研究领域、国家（地区）、发文机构4个维度统计2002-2016年15年间被WoS收录的高质量学术期刊所发表的论文，进而分析解读OA论文的变化情况；最后以Nature为例，以篇均被引次数与高被引论文占比为切入点，对OA论文的质量作简要分析。[结果/结论] 全球OA论文数量逐年增长，尤以中国为典型代表；中国科学院是WoS平台收录论文最多的机构，2016年其OA论文量占据首位，但OA率与主要欧美机构尚有一定差距；生物医学领域的OA实践效果优于其他研究领域。

[Purpose/significance] This paper aims at getting a comprehensive understanding for the quantity and OA ratio of OA papers, and making a preliminary evaluation of these papers. [Method/process] In this paper, we utilized Web of Science Core Collection as the data source and took the four dimensions: publication years, research areas, countries/territories and organizations. We investigated papers published in high-quality academic journals that recorded in WoS from 2002 to 2016. Then, we analyzed and interpreted the changes and trends of OA papers. Finally, we took Nature as an example and analyzed the quality of OA papers from the perspective of citation per paper and highly-cited papers proportion. [Result/conclusion] The number of OA papers in the world have been increasing year by year, especially in China. Chinese Academy of Sciences (CAS) is the institution which has the largest number of papers recorded in WoS, the number of OA papers took the first place in 2016, but the OA ratio still lagged behind major European and American institutions. The OA practice in the field of biological and medical sciences is superior to other research fields.