Net profits increased by £56 million in the first half of 2005, compared with an increase of £47 million for the same period the previous year.
The company's revenues rose by 5.5 per cent to £560 million - a performance that was driven by strong organic growth in its street furniture division and improvement in transport sites.
Despite the figures exceeding the company's targets, JCDecaux said its margins were still being hampered by the weaknesses in the French advertising market.
The group's total earnings before interest and taxes increased by 1.9 per cent to £93 million, which was also ahead of forecasts.
The company specialises in three divisions: street furniture, which uses bus shelters, newspaper kiosks and public lavatories; billboards and transport - which includes advertising in airports and railway stations.
Jean-Francois Decaux, the co-chief executive, said: "Our first-half results for 2005 reflect the softening of advertising conditions in certain European markets as well as the evolution of our business mix, with a growing revenue contribution from the lower- margin transport division."