Axis.TickLabelPosition (Word)

Describes the position of tick-mark labels on the specified axis. Possible return values are xlTickLabelPositionHigh - The top or right side of the chart, xlTickLabelPositionLow - The bottom or left side of the chart, xlTickLabelPositionNextToAxis - Next to the axis (where the axis is not at either side of the chart), xlTickLabelPositionNone - No tick marks.

With ActiveDocument.InlineShapes(1) 
 If .HasChart Then 
 .Chart.Axes(xlCategory) _ 
 .TickLabelPosition = xlTickLabelPositionHigh 
 End If 
End With