Younger men are suffering from "stunted" progress on pay, earning thousands of pounds less than the previous generation, a study shows.
Research by the Resolution Foundation found that men aged 22 to 30 had a pay deficit of £12,500 compared with those born between 1966 and 1980.
This has narrowed the gender pay gap, but for the wrong reasons, said the think tank.
The analysis revealed a shift towards younger men working in lower-skilled jobs, often part-time, which was given as the main reason for the slower pay growth.
The proportion of low-paid work done by young men has increased by 45% since 1993, compared with a fall among young women, said the report.
The foundation said that while the overall story of the UK labour market over the two last decades has been a positive shift away from low and mid-skilled jobs into more high-skilled ones, young men have not fully benefited.
Torsten Bell, executive director at the Resolution Foundation, said: "The long-held belief that each generation should do better than the last is under threat. Millennials (those born between 1981 and 2000) today are the first to earn less than their predecessors.
"While that in part reflects their misfortune to come of age in the midst of a huge financial crisis, there are wider economic forces that have seen young men in particular slide back.
"Millennial men have earned less than the generation before them in every year of their working lives - a pay deficit that adds up to £12,500 by the time they reach 30.
"This is in part due to major shifts in the world of work with many more young men moving into lower-skilled jobs in shops and restaurants, and doing many of those jobs part-time.
"The fact that young women have bucked this trend by moving overwhelmingly into higher-skilled roles is welcome and suggests that the disruptive force of automation has met its match in the forward march of education and feminism."