According to the ATO's SMSF investing in cryptocurrencies guide, SMSFs are not prohibited from investing in cryptocurrencies. However, the investment must:
Be allowed for under the fund's trust deed
Be in accordance with the fund's investment strategy
Comply with Superannuation Industry (Supervision) Act 1993 (SISA) and Superannuation Industry (Supervision) Regulations 1994 (SISR) regulatory requirements concerning investment restrictions
The ATO encourages SMSFs to seek independent professional advice first.