Identification of the cloud in an image is essential in order to remove the noise in the image and improve the quality of the image. Further the masking of cloud in a satellite image is important in order to obtain a clear image taken from a remote sensing satellite. This thesis presents the identification of cloud in a satellite image, to segregate the cloud part of the image from non-cloud part of the same image like soil, vegetation, water by using certain techniques. Region of interest (ROI) selection technique is used to obtain the desired cloud image from the actual image. To obtain cloud image from non-cloud image masking methods such as automatic masking and manual masking are used in ROI selection technique. A suitable image is obtained from the sensor known as ‘Moderate Resolution Imaging Spectroradiometer’ (MODIS). The manual and automatic masked cloud images are compared and the performance of the cloud masking methods is evaluated. The evaluation of the results indicates that the cloud images are possible to obtained by ROI selection technique through automatic masking and manual cloud masking method.