The fund will support small firms in mid and north Wales and provide money to “ambitious local businesses”.
The institutions plan to launch the fund, which will operate independently of the universities, in the first half of 2012,
It will be financed from a “variety of sources” including private equity, the universities said.
In their joint statement, the universities say that the ?2 million figure is an “initial” amount.
The fund still has to be ratified by the governing bodies of the universities and the Welsh government.
Noel Lloyd, the vice-chancellor of Aberystwyth, said: “Universities have a key role in promoting innovation and this is something which is at the very heart of our existing commercial activities.
“As we deepen and broaden the collaboration with our colleagues in Bangor, the time is now right to take a bold step in helping to support early stage companies, looking to invest and grow here in Wales.”
John Hughes, vice-chancellor of Bangor, added: “The launch of this fund demonstrates the firm commitment of both universities to contribute in a very direct way towards the economic development of our region.
University venture capital funds are more prevalent in the US, where New York University launched a $20 million (?12.3 million) fund in June.
NYU gave $2 million of its own money, with the rest to come from donations.
It will be making investments of between $100,000 and $1 million in early stage firms using technologies developed at NYU.
Other US institutions with venture capital funds include Case Western Reserve University in Ohio.