方式1：运用宏代码，如下：

Sub insert()
    Dim i As Integer
    For i = 1 To ActivePresentation.Slides.Count
        ActivePresentation.Slides .Select
        With ActiveWindow.Selection.SlideRange
            .FollowMasterBackground = msoFalse
            .Background.Fill.UserPicture "path" & i & ".jpg"
            End With
    Next

End Sub

方式2：插入–>图片–>新建相册.