What exactly are you asking? Are you asking about treaties named the Treaty of Paris or treaties in Paris? If you're talking about treaties named the Treaty of Paris, there were twenty. If you are refering to all Paris peace treaties, then there were 23.
1. 1229, between Sant Louis and Raymond VII of Toulouse, end of Albigensian crusade
2. 1259, between Henry III of England and Louis IX of France
3. 1303, between King Philip IV of France and Edward I of England
4. 1323, Count Louis of Flanders relinquished Flemish claims over Zeeland
5. 1355, a land exchange between France and Savoy
6. 1515, Alliance between the count of Flander and Francis I of France
7. 1623, between France, Savoy, and Venice against Spanish forces in Valtelline
8. 1634, Between France, Sweden and Heillbronn
9. 1657, established military alliance between France and England against Spain
10. 1763, ended the Seven Years' War/French and Indian War
11. 1783, ended the American Revolutionary War
12. 1784, ended the Fourth Anglo-Dutch War
12. 1796, ended the war between France and the Kingdom of Piedmont-Sardinia
14. 1806, Creation of the confederation of the Rine
15. 1810, ended the war between France and Sweden
16. 1814, ended the war between France and the Sixth Coalition
17. 1815, followed the defeat of Napoleon at Waterloo
18. 1856, ended the Crimean War
19. 1857, ended the Anglo-Persian War
20. 1898, ended the Spanish-American War
21. 1900, ended all conflicting claims between France and Spain over Río Muni
22. 1920, united Bessarabia and Romania
23. 1947, formally established peace between the World War II Allies and Bulgaria, Hungary, Italy, Romania, and Finland
24. 1951, established the European Coal and Steel Community
25. 1952, European Defense communauté (but not signed by France after the 5 other countries did

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26. Peace conference of 1919, atlhough the treaties were not signed in Paris itself.
27. 1973 Paris Peace Accords, ended American involvement in the Vietnam War
That's at least 25... a bit more than your 20..