Ontologies are an essential component of the Semantic Web and in recent times, the significance of modular ontologies is largely increasing due to their superiority over monolithic ontologies. Out of the multiple modularization choices available, the one which guarantees best system design and performance should be applied. Some attributes of modular structure such as cohesion and coupling, determine the goodness of modularization technique applied. Few works are available in the field of assessing modular ontology in terms of cohesion and coupling. Most of such works are either syntax based or do not handle the structure of the ontological hierarchy during evaluation of cohesion and coupling. We propose an approach for analysing cohesion and coupling of modular ontology, which may be used in order to formulate measures for the same. The extent of dependence among the components of an ontology is analysed for quantification, which acknowledges subtle differences among relationship types. Moreover, our approach accounts for structural dependencies in ontology, thus making it a comprehensive model.