The NZX 50 fell 13 points, or 0.1%, to 13,568 in Friday morning trade, declining for the third consecutive session, mainly weighed down by the financial, industrial, and technology sectors.
Traders were cautious ahead of the RBNZ's monetary policy decision next week while anticipating the release of China's inflation data, amid rising global oil prices during June.
However, easing oil prices helped cap the losses as inflation concerns subsided, reducing expectations of an interest rate hike.
The latest data also limited the decline, as consumer confidence in New Zealand hit a three-month high in June, following an improvement in business confidence.
Among the early decliners were Mercury NZ (-1.1%), Fletcher Building (-0.9%), Freightways Group (-0.4%), Infratil (-0.4%), and ANZ Group (-0.3%).
However, the index is heading for a 0.6% weekly gain after being flat in the previous week.