Linda Graff told volunteering charity CSV's volunteer management conference this month that volunteers in both the UK and her own country, Canada, remained "sorely undervalued".
"On the principle that we often do not recognise or value what we have until it is taken away from us, perhaps a volunteer strike would very well demonstrate just how indispensable volunteers have become to our way of life," said Graff.
She added that her suggestion was "tongue-in-cheek".
Graff said volunteering was under threat because of increasing bureaucracy and the fact that younger volunteers tended to want short-term, tailored opportunities.
"Mobilising, engaging and coordinating the efforts of these new volunteers is more complex and time-consuming than ever," she said.
She said it was also likely that the economic crisis would prompt funders to cut spending on volunteer management and promotion.
Mike Locke, director of public affairs at Volunteering England, said a volunteering strike was not realistic. "But as a dramatic piece of rhetoric, it is a good way of drawing attention to the issue," he said. "It can be frustrating getting over to people the power and extent of volunteering."