Tenth of workers want more hours
Research commissioned by the party showed that 330,000 more people are underemployed in the UK than in 2010, including 200,000 with dependent children.
Labour said the study, coupled with a report suggesting that a million workers are on zero-hours contracts - under which they are not guaranteed work from one week to the next - showed how families were facing a living standards crisis.
Shadow work and pensions minister Stephen Timms said: "David Cameron's cost-of-living crisis is being made worse by a surge in underemployment under his failed Government.
"More than one in 10 are now unable to work the hours they would like because this Government strangled the recovery. That's why the real story of the labour market is falling wages, almost a million young people out of work and millions working harder for less.
"David Cameron's out-of-touch Government needs to wake up from its complacency on living standards now."
Labour said research by the House of Commons Library showed that the number of people in employment who were willing to work more hours had jumped from 2.8 million at the start of 2010 to more than 3.1 million this year.
A Department for Work and Pensions spokesman said: "The vast majority of workers - nine out of 10 - say they're not underemployed. It's simply not true to say that there has been a surge.
"The total number of hours people are working continues to rise, and latest statistics showed that the number of vacancies are continuing to increase - up 12% in the past year."
Business minister Matthew Hancock said: "People are now working more hours per week than they were in 2008.
"It's a shame for Labour to talk Britain down on the same day that manufacturing and services have risen, car sales are up again and retail sales are growing at their fastest rate in seven years."
© 2013 Press Association