The intrinsic morphology, mineralogy and gradation characteristics of geomaterials and geosynthetics play a pivotal role in determining their vital geotechnical properties. In view of this, this paper attempts to demonstrate the relevance of advanced digital image analysis for micromorphological characterisation of geomaterials and geosynthetics based on the critical appraisal of pertinent literature. Although many studies have been dedicated to enhancing the current state of practice pertaining to the potential applications of digital image analysis in diverse fields of practical and research requirements, there is a lack of well-established procedures for quality-assured sample preparation, execution of image processing and analysis. In light of inferences gathered from up-to-date literature, this study emphasises the fact that digital image analysis can be an effective complementary tool to conventional methods for physical and micromorphological characterisation of geomaterial and geosynthetics, in view of assessing their macroscale engineering behaviour. © 2018 ICE Publishing: All rights reserved.