Total unemployment fell 33,000 to 2.45 million for the three months to January. Long-term employment, however, increased by 61,000 to 687,000.
Joblessness among 18- to 24-year olds fell by 34,000 to 715,000, while unemployment among over-50s increased by 14,000 to 398,000.
The number of people with Jobseeker's Allowance fell by 32,300 to 1.59 million.
Yet the number of people in work actually fell in the quarter, by 54,000 to 28.86 million.
"One word sums up the latest official jobs figures: confusing," Dr John Philpott, chief economic adviser at the Chartered Institute of Personnel and Development (CIPD), told the BBC.
"Unemployment is sharply down, however you measure it. Yet there also 54,000 fewer people in work, with full-time jobs particularly hard hit.
"The apparent paradox is explained by a very sharp rise of 149,000 in the number of economically inactive people, with the number of students surging by 98,000. Jobless young people are thus turning to study in their thousands to avoid the dole."
Work and Pensions Secretary Yvette Cooper told the BBC: "The fall in unemployment for the third month in a row is very welcome, but we should remain cautious... we plan to increase help to get people back into jobs this year, not cut it back, so we can support the jobs of the future."
