We have studied surface electronic properties of GaAs covered by self-organized InAs dot structures through tunneling spectroscopic measurements. Differential conductance properties on n-type (001) GaAs samples covered with an InAs wetting layer or InAs dot structures were measured by a scanning tunneling microscope operated in air under laser light. The modulation effects on the tunneling properties by the laser irradiation reveals that the surface electronic properties, such as band bending and surface Fermi level, of the n-GaAs sample with the InAs wetting layer are very similar to those of a bare n-GaAs sample. In contrast, additional deposition of InAs over the wetting layer, which forms InAs dots, leads to a drastic change in the electronic properties near surface.