Copper futures for June declined by Rs 1.55, or 0.38%, to Rs 408.55 per kg in 177 lots.
At the Multi Commodity Exchange (MCX), the April contract fell by Rs 1.50, or 0.37%, to Rs 401.85 per kg in 3,998 lots.
Extending its weakness, prices fell as speculators engaged in trimming their positions.
A weak trend overseas as worse-than-estimated US economic data spurred concern that growth is slowing in the world's second-biggest user and increasing stockpiles of the metal, mainly weighed on the copper futures trade here.
On the London Metal Exchange (LME), the three-month contract traded 0.40% lower at $7,356.25 per tonne, lowest level since August 3.
