The corporation's section 179 depreciation does not appear on IRS Form 1120-S, U.S. Income Tax Return for an S Corporation. This is because the Section 179 depreciation is not deducted on the Corporation's 1120-S return. It is passed through to the shareholders on Schedule K-1 (Form 1120-S), Shareholder’s Share of Income, Deductions, Credits, etc.
Per IRS Instructions for Form 1120-S U.S. Income Tax Return for an S Corporation, on page 17:
Don't include any section 179 expense deduction on this line. This amount isn't deducted by the corporation. Instead, it is passed through to the shareholders in box 11 of Schedule K-1. However, reduce the basis of any asset of the S corporation by the amount of section 179 expense elected by the S corporation, even if a portion of that amount can't be passed through to its shareholders this year and must be carried forward because of limitations at the S corporation level. See Regulations section 1.179-1(f)(2).
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