Автор: http://www.swissdelphicenter.ch

uses
  comobj;

procedure TForm1.Button2Click(Sender: TObject);
var
  PowerPointApp: OLEVariant;
begin
  try
    PowerPointApp := CreateOleObject('PowerPoint.Application');
  except
    ShowMessage('Error...');
    Exit;
  end;

  // Make Powerpoint visible
  PowerPointApp.Visible := True;

  // Show powerpoint version
  ShowMessage(Format('Powerpoint version: %s', [PowerPointApp.Version]));

  // Open a presentation
  PowerPointApp.Presentations.Open('c:\MyPresentation.ppt', False, False, True);

  // Show number of slides
  ShowMessage(Format('%s slides.',
    [PowerPointApp.ActivePresentation.Slides.Count]));

  // Run the presentation
  PowerPointApp.ActivePresentation.SlideShowSettings.Run;

  // Go to next slide
  PowerPointApp.ActivePresentation.SlideShowWindow.View.Next;

  // Go to slide 2
  PowerPointApp.ActivePresentation.SlideShowWindow.View.GoToSlide(2);

  // Go to previous slide
  PowerPointApp.ActivePresentation.SlideShowWindow.View.Previous;

  // Go to last slide
  PowerPointApp.ActivePresentation.SlideShowWindow.View.Last;

  // Show current slide name
  ShowMessage(Format('Current slidename: %s',
    [PowerPointApp.ActivePresentation.SlideShowWindow.View.Slide.Name]));

  // Close Powerpoint
  PowerPointApp.Quit;
  PowerPointApp := UnAssigned;
end;