A LED (Light Emitting Diode) bulb structure includes a base, a plurality of fins and a shell. One end of the base is electrically connected to a power source, and the other end of the base is used for holding a LED light source. The fins are disposed on a surface of the base. The shell encloses the fins, and the shell includes a plurality of first heat-dissipation holes and a plurality of second heat-dissipation holes. The first heat-dissipation holes are arranged around the shell and corresponding to the fins for allowing airflow entering the first heat-dissipation holes to directly pass through each of the fins corresponding to each of the first heat-dissipation holes. The second heat-dissipation holes are arranged around the shell and disposed above the first heat-dissipation holes for enabling the first heat-dissipation holes and the second heat-dissipation holes to conduct thermal convection.