Click and drag over the cell or cells to which you want to change alignment.
Click the Align Left button to align text to the left, the Center button to center text, or the Align Right button to align text to the right.
PowerPoint applies the new alignment. In this example, the cell text is centered horizontally in the cell.
By default, when you type table text, the text is aligned to the left in each cell. You can quickly change the alignment using the alignment buttons on the Formatting toolbar. You can also adjust the vertical alignment of your table text. By default, PowerPoint vertically aligns cell text to appear at the top of the cell, but you can set the alignment to the center or bottom of the table cell.
Selecting the Entire Table
To quickly select all the cells in your table for editing, simply click the table border. You can also click the Table button on the Tables and Borders toolbar and then click Select Table .
To change the vertical alignment of the text in selected cells, click the Tables and Borders button on the Standard toolbar.
Click Align Top to align text to the top of the cell, Center Vertically to center the text vertically in the cell, or Align Bottom to align the text to the bottom of the cell.
PowerPoint applies the new alignment. In this example, the cell text is centered vertically in the cell.
Closing the Toolbar
When you finish editing your table, you can close the Tables and Borders toolbar by clicking the Tables and Borders button on the Standard toolbar, which toggles the toolbar on or off. You can also close it by clicking the toolbar's Close button.