What is the opposite of interestante in spanish?

The opposite of "interesante" (interesting) in Spanish depends on the context:

If you mean "not interesting", the opposite is:

* Aburrido/a (boring)

* Insípido/a (tasteless, dull)

* Monótono/a (monotonous)

* Desinteresante (uninteresting)

If you mean "uninteresting" in a specific way, you could use:

* Insignificante (insignificant)

* Trivial (trivial)

* Irrelevante (irrelevant)

Example:

* "La película era interesante." (The movie was interesting.)

* "La película era aburrida." (The movie was boring.)

The best opposite for "interesante" will depend on the specific situation and what you want to emphasize.