The Council of Mortgage Lenders (CML) also said in the last quarter of 2015 more first-time buyers purchased properties in the region than at any time since 2006.
The organisation publishes data on behalf of banks and building societies.
It said 3,700 mortgages worth £380m were taken out in 2015's final quarter.
That is a rise of 3% on the same quarter in 2014 and 6% on the previous quarter, with first time buyers accounting for 2,100 of the loans.
Derek Wilson, the CML's Northern Ireland chair, said: "Home lending in Northern Ireland for the quarter rose to its highest level since mid-2007.
"It is welcome to see more first-time buyers purchasing their first home in this period than any other quarter since 2006."
The CML is forecasting the "upward trend" to continue in 2016, despite issues around a supply of new properties.
Meanwhile, the latest property survey by the University of Ulster has said 2015 saw the strongest year for price growth since the 2008 crash.
Average prices are up by 9% on 2014, "indicating that strong market conditions are prevailing."
Property prices are 40% below what they were at the peak of the market in late 2007.
Mortgage lending in Northern Ireland has hit its highest level since the property market was heading for its peak in 2007, according to new data.