Soil inoculation with active microorganisms is a key step for the success of bioaugmentation for on-site restoration of contaminated soils. Introducing the desired microorganisms as biofilm can favor their activity and survival once in soil. A key parameter for biofilm growth is the choice of the carrier material. In the frame of pesticides-contaminated agricultural soils bioremediation using bioaugmentation, the activity, viability and biodiversity of a bacterial MCPA- and 2,4-D-degrading consortium grown on various carrier materials was studied. For this, three natural materials (zeolite, pozzolana, oyster shell) as raw or modified (surface covering with Ca/fe-Layered Double Hydroxides (LDH)) carrier materials were used to support the development of the degrading consortium. Such an LDH composition was chosen as, if validated as non-toxic to bacteria, it will allow the introduction of nutrients into its structure to improve the bioaugmentation process. All carrier materials, modified or not, allowed the growth of a pesticide-degrading biofilm whose biodiversity mainly depended on the carrier material rather than on surface modification, even if the presence of LDH on zeolite increased (Pseudomonas) or decreased (Azohydromonas, Sphingopyxis) the proportion of some bacterial strains. LDH was non-toxic at the concentration (10 g L-1) used for carrier material surface modification, and lead to MCPA adsorption. All biocomposites, i.e. biofilm grown on a carrier material, had a MCPA- and 2,4-D-degrading activity, whatever the carrier material or LDH presence/absence. Pesticide biodegradation was rapid (DT50 < 1.5 days with initial [MCPA]=5 mg L-1) and mineralization (radiorespirometry experiments with labelled 2,4-D) was observed. Several MCPA-degrading strains (Pseudomonas, Rhodococcus, Cupriavidus, Variovorax, Ralstonia, Aminobacter) were isolated from the zeolite-biocomposite. In conclusion, biocomposites made from selected carrier materials and consortia with the desired biodiversity and degradation activity could improve soil bioaugmentation approach. Modification of the surface of the carrier material could be a mean to further improve this biotechnology.