An aromatherapy nebulizing diffuser includes a bottom shell, a electric fan mounted in the bottom shell, a fluid container supported on the bottom shell, a cap caped on the fluid container, a oscillator mounted in the fluid container for oscillating a contained aromatic fluid into a fine mist of aromatic fluid droplets, and an air guide mounted in the fluid container and having a horizontally extended air outlet that mates with a curved inside wall portion of the cap to create a curved air flow path that guides the intake flow of air to strike against the inside wall of the cap and the container body and to further increase the air pressure for lifting the created fine mist of aromatic fluid droplets efficiently.
