The work perfomed to characterize the elemental composition and functional groups of humic acids extracted from four lombricompost cow dung, filter press cake of sugar cane, coffee pulp and grass residue the total content of essential elements and its distribution in the humic and no humic fractions were determined. It was evalued the effect of two concentrations of humic acids (150 and 300 ppm) upon seed germination of maize, cotton and tomat. There were found differences in the elemental composition (CHON) and functional groups (COOH, OH phedic and carbony) of the humic acids atributed to variations in composition of the original substrates. The lombricompost of cow dung showed higher oxidation values (O/H = 0.49) than the lombricompost of filter press cake of sugar cane (0.40) sugering a higher grade of humification of the first. The grass residue showed higher contribution to the CIC (COOH + OH = 9. O me/g) than the coffe pulp (7. 1 me/g) the total essential elements were concentrated in the remanent residue, with lower content in the water and 0.1M HCL solutions; the fulvic and humic fractions had very low content of these elements. The humic acid at the concentrations tested did not have any effect on the germination of maize and cotton, and depressed the germination of tomato seeds.