Pattern reversal visually evoked potentials (VEPs) were recorded from 439 infants and young children ranging in age from 1 month to 5 years in response to large and small checks. Qualitative analysis of the VEP wave form showed that the first major positive component, P 1, is consistently present at all ages, while the frequency of occurrence of later positive components is more variable. The proportion of infants showing late positive components increases with age; by 1 year, the frequency of occurrence of late components for large checks is more adult-like than for small checks. The latency of P 1 was analyzed quantitatively. Results showed that P 1 latency decreases rapidly during the first year of life for both large and small checks and that the time course of the latency change differs as a function of check size. VEPs to large checks attain adult-like P 1 latency values by about 1 year of age, while the P 1 latency of VEPs to small checks has still not reached adult levels by 5 years of age. Data from 12 infants tested longitudinally between 1 and 7 months of age using both checkerboards and square wave gratings show no difference in P 1 latency between checkerboards and gratings comprised of large (30–240 min) pattern elements, but for patterns with small (7.5 and 15 min) elements, P 1 latency to checks is significantly longer than P 1 latency to stripes. These results are explained on the basis of the difference in the fundamental spatial frequency between checks and stripes.