A group of 50 skilled readers and a group of 50 less-skilled readers of Grade 5 matched for age and intelligence and selected on the basis of their proficiency in reading comprehension were tested for their competence in word reading and the processes of attention, simultaneous coding, successive coding and planning at three levels, i.e., perceptual, memory, and conceptual in order to study the relationship of attention with the processes of coding and planning at these levels and their contribution to the reading achievement of children. Results of t test and correlational analysis suggest that all the processes are related significantly to the two skills of reading at conceptual level, whereas, successive coding and planning are related significantly to reading at perceptual and memory level also. Attention, the basic cognitive process, at the same time showed significant relationship with simultaneous processing at all the three levels, whereas, conceptual attention was found to have significant relationship with successive processing at memory level and planning at conceptual level. The results have been discussed in terms of functional aspects of the brain structures underlying cognitive activities including reading and suggestions have been made for the remediation of reading difficulties of children.