On wages, the survey said that only 40.3 per cent earned more than $US2000 per month.
Of the rest, 14.5 per cent earned between $US1000 ($A1330) and $US2000, 24.6 per cent earned between $US300 ($A400) and $US1000 and 20.6 per cent earned $US300 or less.
Forty-one per cent said they had experienced delays in being paid, a figure which rose to 79 per cent in Malta, 75 in Turkey, 74 in Romania, and 96 in Gabon, 95 in Bolivia and 94 in Tunisia.
Of those who said they had been victims of violence, 51 percent had been attacked by fans, 25 percent by fellow players and 12 percent by club officials or coaches.
Democratic Republic of Congo was the worst country for both violence and threats of violence from supporters on match days.
Scotland was surprisingly in second place in the latter category, with Brazil fifth and Italy sixth.
For threats of violence on non-match days, Italy was by far the worst country, with 24 percent of players saying they had been menaced by fans.
Fifteen percent of players said they had been victims of bullying or harassment, while 7.5 percent alleged discrimination based on ethnicity, sexuality or religious beliefs.
A lack of job security was also a problem with the average contract length of 22 months while eight per cent of players said they did not have a contract at all. Just under 10 per cent of players said they had suffered physical violence off the field, either from fans, team mates or club management, and 16 per cent said they received threats of violence.
Clubs sometimes bullied players when they wanted them to leave and six per cent said they had been made to train apart from the rest of the squad.
THE 'OTHER' WORLD OF PROFESSIONAL FOOTBALL:
* Only 40.3 per cent of those survey earned more than $US2,000 ($A2,669) per month. Of the rest, 14.5 per cent earned between $US1,000 ($A1,335) and $US2,000 ($A2,669), 24.6 per cent earned between $US300 ($A400) and $US1,000 ($A1,335) and 20.6 per cent earned $US300 ($A400) or less.
* Less than two per cent earn more than $US720,000 ($A960,984) annually.
* More than 40 per cent said they had experienced delayed payments at some point in the last two years.
* The average length of a player's contract was between 22 and 23 months.
* Of the players whose last move involved a transfer fee, 29 per cent said they were forced to change clubs against their will.
* Eight per cent of players said they did not have a written contract with their club, a figure which rose to 15 per cent in Africa.
* In Croatia and the Czech Republic, more than 90 per cent of players were regarded as self-employed or had a civil law contract - denying them the protections afforded to employees.
(Key findings of the world players' union FIFPro survey of nearly 14,000 professional footballers around the world).