"On 9 November 2009, the grand slam committee administrator determined Serena Williams had committed the grand slam major offence of aggravated behaviour for her misconduct at the 2009 US Open," International Tennis Federation (ITF) said in a statement.
The world number one could face suspension if she commits another 'major offense' at any Grand Slam in the next two years.
However, if she manages to get through the next two year without committing any offence, then the fine will be reduced to 82,500 dollars.
Grand Slam Committee, representing Wimbledon and the US, French and Australian Opens took this decision after looking into the incident for two months.
During the 2009 US Open semifinals, Williams indulged in a foul-mouthed outburst. She lashed out at a lineswoman inviting a maximum on-site fine of 10,000 dollars and charges of code of conduct violation.