It's not big and fancy like the Louvre or Le Grand Palais. But if you like flowers and/or sculptures, I highly recommend stopping by (if you're lucky enough to have a sunny day in Paris!)
If you're just interested in the gardens, you can pay just 1€ to enter and explore them at your leisure - the cost to enter the full museum and the gardens is 9€.
If you're lucky enough to be a student in the EU ages18-25 years old or a French teacher (random?) congrats you get in for free!
Being a poor graduate student, I stuck to the gardens. The flowers were in full bloom, although I can only imagine how much more spectacular they'd be if I'd made it there a few weeks earlier - by the time I'd arrived most of the roses had seen their peak.
Several of Rodin's sculptures are outside in the gardens. So unless you're a massive Rodin fan, or really into sculptures, I think the 1€ ticket for the gardens is all you need to enjoy your visit. I definitely recommend waiting for a sunny, or at least a quasi-sunny day if you're lucky enough to come across one while you're in Paris.
And make sure to explore the full grounds - after visiting the gardens toward the front, there is a back area with a large fountain, and some wooded areas that are definitely worth exploring!
79, rue de Varenne - 75007 Paris
Open daily, except Mondays
10am to 5.45pm - open Wednesdays until 8.45pm
(Last tickets sold at 5.15pm)
Metro : Varenne (line 13) or Invalides (line 13, line 8)
R.E.R : Invalides (line C)
Bus : 69, 82, 87, 92
Vélib' : 9, Bd des Invalides
Car parks : Bd des Invalides
Tel: + 33 01 44 18 61 10