The numbers reveal that highly paid employees in Cornwall earn about £ 18,000 a year more than those at the bottom of the pay scale.
The Egality Trust said that figures from the Office for National Statistics, which reveal a gap of nearly £ 25,000 between the highest and lowest incomes in the UK, "paint a picture depressing income inequality ".
In Cornwall, the average weekly earnings of the top 20% of full-time earners are now double that of the bottom five, a difference of £ 17,982.
The figures for workers who live in the region use averages, rather than averages, to avoid being skewed by particularly low or high wages.
They show that the top 20% paid on average £ 690 a week, or £ 35,875 a year.
For low wages, the weekly wage was £ 344 to £ 17,893 a year.
The average full time employee in Cornwall works 37.5 hours per week for a median annual salary of £ 24,508.
Figures refer to base salary and do not include bonuses or overtime.
The wage gap between Cornwall's highest and lowest incomes is below the UK average.
In the United Kingdom, the average annual salary of the top 20% of the highest paid is 2.2 times higher than that of the lowest paid.
The highest-paid people earn £ 44,533 on average, compared to £ 19,874 for their less-paid counterparts.
It's in London that the gap is the largest, the highest paid paying £ 56,300, nearly £ 33,000 more than the low salaries.
The most equal Wales is where the richest 20% earned 2.1 times the fifth wage.
Wanda Wyporska, Executive Director of the Charity Equality Trust, said: "Like the gender pay gap, the gap between the lowest-paid workers and high and low wages is not reduced enough quickly.
"But it is an even bigger scandal, because the evidence shows that in countries with high inequality, such as the United Kingdom, violent crime, physical and mental health problems, infant mortality and levels of confidence and education are lower.
"By continuing to ignore inequalities, policymakers do not really realize the social and economic potential of this country."
According to the Trades Union Congress, one in nine British workers are in precarious and poorly paid "precarious work", including those under contract at zero hours and self-employed workers earning less than the minimum wage.
Secretary General Frances O. Grady said, "Workers deserve to receive a fairer share of the wealth that they create." It's not normal for millions of people to have trouble reaching both ends, while those in the most expensive pockets earn checks.
"We have to rebalance the balance of power in our economy.
"It means giving workers new rights so that they can access the protection of a union at each workplace and negotiate for better wages and conditions in all industries."