Australian Index Investments (Aii) will list its first sector-specific exchange-traded fund (ETF) on Thursday 25 March.

The Aii S&P/ASX 200 resources fund is the first of six sector ETFs to be listed on the Australian Securities Exchange (ASX).

ASX general manager equity markets Richard Murphy welcomed the growing range of ETFs.

"We think it is a wonderful development because, at heart, it is a really simple product," Murphy said.

Aii has engaged PennyWise Investments to provide research on the sector the ETF tracks and PennyWise has given the resources sector a market weight rating.

Research provider Aegis, which provides analysis of the structure of ETFs including how well they track the underlying indices, also welcomed the expansion of the range. However, it said these funds are not always as diversified as similar funds in overseas markets.

"The problem with sectors is that in Australia we are heavily weighted to one stock," Aegis head of sales and relationship management Craig Northey said.

The resources ETF, like the index it tracks, leans heavily towards BHP Billiton, which makes up 43.7 per cent of the total fund.

The top three holdings are completed by Rio Tinto, which takes up 9.8 per cent, and Woodside Petroleum, which makes up 7.1 per cent of the fund.

Aii will also list five ETFs that will track the financial, financial excluding Australian real estate investment trusts, energy, industrials, and metal and mining sectors.

These ETFs will be listed in the coming weeks.