Online boost
The £308m profits figure was its lowest first-half profit since 2010, and down from £375m last year. However, the figure was still ahead of analysts' expectations of about £293m.
Sainsbury's said food sales had declined by nearly 1%, but clothing performed strongly, with sales up by close to 10%.
Sales at supermarkets fell by just over 2%, driven by food deflation, lower like-for-like volumes, and "customers shopping across multiple channels".
However, convenience stores delivered sales growth of nearly 11%, while online grocery orders delivered sales growth of 7%.
The latest research from Kantar Worldpanel found that the firm was the only major chain to see sales rise in the 12 weeks to 11 October, lifting its market share to 16.1%.