Telecom is trying to get Vodafone's new advertising campaign changed or pulled and has applied for a High Court injunction.
Telecom spokesman Andrew Pirie said the company believes aspects of Vodafone's SuperNet advertising were "misleading to consumers and ... therefore in breach of the Fair Trading Act".
The advertising describes Vodafone's infrastructure as "the best fixed-line network".
A telephone conference for the case has been scheduled before Justice Geoffrey Venning this afternoon.
The Herald understands Telecom also takes issue with Vodafone calling its cable network in Wellington and Christchurch "ultra-fast broadband".
This network was previously owned by TelstraClear.
A Vodafone spokeswoman said the company would be issuing a statement on the matter soon.
- By Hamish Fletcher
