With the objective to verify the influence of maize seed size and shape upon its phisiological quality, during six storage periods (zero, 90, 180, 270, 360 and 450 days), one work was conducted in the Embrapa Maize and Sorghum Research Center at Sete Lagoas, State of Minas Gerais, Brazil. Sixteen seed lots of the double cross hybrid BR 201 and four seed lots of the double cross hybrid BR 205 obtained from five Seed Companies were classified according to the following categories: round sieve , S 18 (18 / 64? x 3/4?); and flat sieves: S 24 (24/64?), S 22 (22/64?), S 20 (20/64?) and S 18 18/64?). The experimental design was randomized complete block with five treatments and three replications. For both hybrids and for all seed grades, the results showed index of germination above the minimum accepted for sale in Brazil (85%) during all storage period, except the seed lot sieve S 24, hybrid BR 201 after 270 days of storage. When was compared differents graded seeds lots of the same hybrid itself, were observed that the most graded seed size showed similarities storage potential except of size S 24, hybrid BR 201 and size S 18R hybrid BR 205.