The report, which focuses on the 2006-07 season, revealed eight out of the 12 SPL clubs made a profit and is attributed to an overall reduction in transfer fees and wages.
"The picture continues to look bright for Scottish football with many clubs now displaying shrewd business acumen," said PWC partner David Glen.
Overall, turnover increased by three per cent and the clubs collectively generated profits of £3million, compared to the previous season's combined losses of £9.4million.
Wages rose, with the Old Firm accounting for more than half of the £100million total.
Celtic showed the most impressive profit, with a surplus of more than £15million.
The club also benefited from lucrative pre-season trips to Japan, Poland and North America. Hibernian's finances also made impressive reading but Edinburgh rivals Hearts made a loss of almost £13million mainly due to a heavy wage bill of £12.5million.
St Mirren, who won promotion to Scotland's top flight in the previous season, witnessed a huge increase in crowds of 48%, helping them achieve a large rise in turnover.
Even relegated Dunfermline still managed a large increase in turnover of 77%, partly as a result of a run to the Scottish Cup final.
Seven of the clubs reduced their debts, with Falkirk and Inverness operating with no debt.