You'll need to link those charts.
Create the charts in Excel -- copy them -- then in PowerPoint, choose Edit |
Paste Special | Paste as Link.

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Geetesh Bajaj, Microsoft PowerPoint MVP
http://www.indezine.com
http://www.ppted.com
> There're charts in 30 slides in power point, their's data source are
> constantly updated in excel. How to auto update the charts in each slide
> without copy them from excel?