Cloud computing is a new technology which comes from distributed computing, parallel computing, grid computing and other computing technologies. In cloud computing, the data storage and computing are not in the local computer and server but in the amount of computers distributed in the internet. Several distributed file systems are used over the cloud because the cloud itself includes large numbers of commodity-grade servers, harnessed to deliver highly scalable and on-demand services. This paper is to discuss about two distributed file systems Google File System (GFS) and Hadoop Distributed File System (HDFS) and compare them by making various use of parameters.