In order to examine the sensori-motor correlation in infants, we recorded the somatosensory evoked magnetic fields to tactile stimulation by using a 37-channel magnetoencephalograph. Twelve healthy infants were examined at palmar grasp stage and pincers grasp stage. Air-tapping stimulation of the right thumb was performed. Three distinct components (W1-3) emerged, W3, with a latency of approximately 100 ms, being the most prominent. As infants grew up, the correlation coefficient and the amplitude of the equivalent current dipole of W3 for the thumb increased. These developmental changes may be attributable to increases in the stability and reproducibility of the cortex in response to somesthetic inputs. Moreover, this change along with motor development supports the presence of a sensori-motor correlation in infants.