Thematic investing is on the rise amongst ASX ETF investors.
ETF providers are consistently coming up with newly designed funds to track niche areas of the market.
For examples of this, look no further than the recently listed Betashares Space Industry ETF (ASX: RCKT).
After listing in mid-May, the fund has already rocketed (excuse the pun) 13%.
However it wasn't the only thematic fund to perform well during May.

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Why target thematic ASX ETFs?
Thematic ASX ETFs can offer investors a simple way to back powerful long-term trends.
Popular themes include artificial intelligence and cybersecurity to clean energy and biotech.
Rather than picking individual winners, investors gain exposure to a basket of companies positioned to benefit from a particular theme.
This can help diversify and spread risk while capturing broad industry growth.
These funds can also provide valuable insight into market sentiment, as strong inflows often signal growing investor confidence in a sector or economic trend.
However, thematic investing is not without risks.
Popular themes can become crowded, valuations may become detached from fundamentals, and trends that appear transformative today may fail to deliver the expected returns.
With that in mind, here were three of the top performing funds during May.
Global X Cybersecurity ETF (ASX: BUGG)
This ASX ETF was a market winner during the month of May.
In the last four weeks, it has risen an astonishing 42%.
The fund seeks to invest in companies that stand to benefit from the increased adoption of cybersecurity technology, particularly those whose principal business is in the development and management of security protocols preventing intrusion and attacks on systems, networks, applications, computers, and mobile devices.
At the time of writing, it is made up of roughly 28 holdings, with the majority based in the US.
Global X China Tech ETF (ASX: DRGN)
Another high performing ASX ETF during May was the China focussed fund from Global X.
It has risen more than 13% over the last 4 weeks, driven by semiconductor and AI tailwinds.
The fund offers access to 20 leading Chinese technology companies listed in Hong Kong and Mainland. With a rules-based selection process across 15 core sectors including semiconductors, robotics, software, and internet platforms, DRGN captures China's strategic push into self-sufficient innovation.
Global X Semiconductor ETF (ASX: SEMI)
It has been a similar story for this Semiconductor focussed ASX ETF.
It has risen by more than 25% in the last month.
The fund seeks to invest in companies that stand to potentially benefit from the broader adoption of tech-enabled devices that require semiconductors. This includes the development and manufacturing of semiconductors.