Ronaldo to the Australian top flight, while admitting it might not be able to compete financially with rival offers for the disaffected Manchester United star.
Ronaldo's future at United is up in the air after he said he felt "betrayed" by the Premier League club and had no respect for its manager Erik ten Hag in an interview with Piers Morgan.
Townsend told Australian media on Thursday that he had made an offer to Ronaldo's agent, Jorge Mendes, in case Ronaldo parts ways with United.
"(Ronaldo) said he wasn't getting any love and respect at Manchester United but we'll certainly give him plenty of love and respect in Australia," Townsend said in comments published by News Corp.
"We might not be able to compete financially with other offers but we can compete in other ways."
Ronaldo's former United team mate Nani joined A-League club Melbourne Victory this season.
Ronaldo, the leading scorer in the history of men's international football with 117 goals in 191 official matches, is preparing to lead Portugal in Qatar in his fifth World Cup.
"Obviously it's a long shot but we've certainly got a compelling proposition for him here in Australia to consider," Townsend told local radio station SportsFM earlier on Thursday.