The Australian Competition and Consumer Commission alleges Samsung’s adverts made “false” claims about using its phones while swimming and surfing.
The ACCC says it has reviewed more than 300 Samsung adverts before launching its legal action.
Samsung says it will defend the case and stands by its adverts.
In its statement, the ACCC says Samsung adverts depicted phones being exposed to seawater and swimming pools and claimed that this would not affect the device during its working life.
Although Samsung adverts say its phones have an IP68 water resistance, the ACCC says this rating does not cover salt water or that found in swimming pools.
Samsung’s own website advises people against using the Galaxy S10 in a swimming pool or on the beach.
The ACCC says Samsung has not done enough testing to make its advertised claims about the longevity of its products.