Around 435,000 people are being paid less than the living wage in Scotland, an increase of more than 70,000 from an estimated 360,000 in 2012, KPMG said.
The wage is a benchmark based on the amount an individual needs to earn to cover the basic costs of living. It is set at £8.55 an hour in London and £7.45 an hour in the rest of the UK and is voluntary for employers to adopt.
It is above the minimum wage and supporters believe it will boost living conditions if adopted by employers.
In April, the Scottish Government implemented a Scottish Living Wage of £7.45 for public sector workers and encourages private sector employers to follow guidelines set out by the Scottish Living Wage Campaign.
The Labour leader Ed Miliband said if his party win the next General Election his party will offer firms a 12-month tax break in 2016 if they agree to pay the living wage.
The proportion of Scottish workers paid below the figure is 20%, slightly below the rest of the UK where 21% of employees are paid less than the living wage, according to the KPMG research.
In Scotland, the areas with highest proportion of workers paid below the living wage are Dumfries and Galloway at 36%, Clackmannanshire at 29% and East Renfrewshire at 20%.
Craig Anderson, senior partner at KPMG in Scotland, said: "Low pay is a real problem in Britain, particularly at a time when the cost of living is rising at a faster rate than earnings. This was underlined by the Social Mobility and Child Poverty Commission recently. People on less than the Living Wage can seriously struggle to make ends meet.
"Although we welcome the findings which show Scotland still has a lower proportion of jobs paying under the Living Wage than most UK regions, the increase on last year is disappointing and suggests there is still more to be done to ensure individuals and their families are able to afford a basic standard of living.
"For many businesses, paying the Living Wage rate need not actually cost any more. At KPMG, we have found that better staff performance and motivation combined with lower absenteeism and turnover cancels out the extra salary costs."
The research by KPMG and Markit analysed around 182,000 returns from the Office for National Statistics' Annual Survey of Hours and Earnings.