The present study had two aims: (1) to examine kindergarten (Kg) and first grade (G1) children's early word structure knowledge, that is letter, phonological, morphological, and orthographic knowledge, and (2) to provide evidence of specific links between these various types of knowledge and word reading and spelling performance assessed in G1. A short longitudinal study was conducted with French-speaking children. Beyond phonological and morphological knowledge, identified here as in many other studies, the results provided evidence of a level of orthographic knowledge in the Kg children who exhibited an ability to process graphotactic constraints (i.e., legal combinations of letters). Moreover, whatever the type of items (affixed, pseudo-affixed, regular, or irregular words) being processed, either in reading or in spelling, letter naming was seen to be the strongest predictor of reading and spelling performance. The second important predictor related to phonological knowledge and more particularly phoneme extraction as a proximal predictor. Morphological knowledge appeared to be less important, and finally, the smallest contribution was made by orthographic knowledge.