The adoption of agroforestry systems or reforestation programs contributes to the economy of a region in a sustainable way, since the adopted species can be exploited by the cosmeceutical and pharmaceutical industries. For the establishment of plant species in a given area, studies are needed on the interaction that can develop between them, with emphasis on research on allelopathy. Given the above, the aim of this study was to evaluate the allelopathic effect of the aqueous extract of leaves of the native species Piptadenia moniliformis on the initial development of the forest species Amburana cearensis. The aqueous extract was used at different concentrations. (0 - water, 25, 50, 75 and 100%), adopting a completely randomized design. The following characteristics were evaluated: emergence percentage, emergence speed index, mean emergence time, shoot and root length and total shoot, root and total dry part of normal seedlings. The 100% concentration of the aqueous extract of P. moniliformis leaves reduced the emergence percentage of A. cearensis seedlings. A smaller number of normal seedlings was observed at concentrations of 75 and 100%. The initial development of seedlings was hampered by the increase in extract concentrations. The aqueous extract of fresh leaves of P. moniliformis provides a negative allelopathic effect for both emergence and early development of A. cearensis seedlings, therefore intercropped cultivation among the forest species is not recommended.