It was studied the effect of calcium fertilization and sowing time difference of drought season peanut, in the seed yield and physiological quality in the seed comercialization. The experiment was installed in field conditions in a Dark Red Latosol, loamy texture, previously cultivated with corn, at Experimental Farm - UNESP - Campus of Ilha Solteira - Selvíria-Brazil. The experimental design utilized was randomized blocks, in factorial, four replications. Four sowing times, cultivar Tatu 53, (E1 - 21/01, E2
-04/02, E3 - 18/02 and E4 - 04/03), arranged with four calcium level (Ca1 = 0kg calcium/ha, Ca2 = 45kg calcium/ha, Ca3 = 90kg calcium/ha and Ca4 = 135kg calcium/ha), applied at the sowing time into the furrow, using dolomite lime with PRNT 90,1% (21% CaO and 18% MgO), were studied. The fertilization consisted in the application of 10kg of N/ha, 75kg of P2O5/ha and 25kg of K2O/ha. It was determined the seed yield, 100 seeds weight and seed physiologic quality (germination and vigor). The calcium fertilization did not affect the 100 seeds weight, as seed yield, but provided a larger germination percentage and more vigorous seeds. The physiological seed quality was smaller at the time of lower pluvial precipitation. The seed yield was reduced in later sowing. The drought season peanut crop for seed production, when sowed late it should be added to the irrigation. Sowing of drought season peanut in beginning of the second fortnight of January provided better as yield as quality seeds. The application of 45kg calcium/ha into the furrow was sufficient to provide better quality seeds.