Using the observations of LASCO aboard SOHO in the interval from Mar. 1997 to Dec. 2003, 302 earth-directed halo CMEs are selected and the source regions are located in MDI synoptic charts. A statistical analysis has been made with the emphasis on the CMEs' largescale source regions as well as the correlation between CMEs and solar surface activity. The statistics show that CMEs are intrinsically related to surface activity. Four groups of CMEs' large-scale source structures are identied on the photosphere. They are: Ⅰ, Extended bipole regions (EBRs) with long magnetic neutral line; Ⅱ, Closely packed active regions (ARs); Ⅲ, Large-scale magneticux of the same polarity runs through the opposite hemisphere, along the boundary there appears transequatorial laments; Ⅳ, Between two EBRs with long lament. The result shows that CME-associated source activity is closely related to the types of large-scale magnetic structures.