A compacting and injection mold for a fiber preform is for use in fabricating a turbine engine guide vane out of composite material. The mold includes a shell forming a trough that is to receive the fiber preform and that is closed in leaktight manner by bottom and top covers, compacting blocks arranged inside the trough each having a surface pressing normally against a surface of the fiber preform that is to be compacted, and closure blocks arranged inside the trough. Each closure block has a surface pressing normally against a surface of a compacting block and does not have a surface in contact with the fiber preform.