The moniliasis, caused by Moniliophthora roreri Cif & Par, has become the principal disease limiting cocoa production in Colombia and other countries. With the objective of exploring alternatives for the biocontrol of this disease, fungi and bacteria isolated from cocoa fruits and rhizospheric soil from plots planted to cocoa trees were evaluated for their antagonism against M. roreri. The evaluation was conducted in Petri dishes containing PDA, by placing in the center of the plate a 5 mm PDA disk colonized by the pathogen and at 3 cm of the edge, on the X and Y axis, each of the isolated microorganisms. The isolates which initially showed antagonism were then evaluated in vitro for their capacity to inhibit the growth and sporulation of M. roreri. The results indicated that of the 53 isolated microorganisms, seven showed antagonism against M. roreri and among them the most effective were the fungi H5 and H20 and the bacteria B3, the fungi for the restriction of the growth and sporulation and the bacteria for the growth. The fungus H20 totally inhibited the growth of M. roreri. These results generate the possibility that these promissory isolates can be incorporated to the management of the disease under field conditions. According to the morphological characterization and the biochemical tests both fungi belong to the genus Trichoderma and the bacteria to the genus Bacillus.