Cardiff second row Davies sustained the injury during training on Tuesday and he will be replaced on the bench this weekend at the Millennium Stadium by 48-times capped Ospreys forward Jonathan Thomas.
Also withdrawn from the squad this week is Scarlets back Morgan Stoddart, not in the matchday 22 to face the Pumas.
Stoddart has a hamstring tear which will see him in rehabilitation for up to a month.
"Bradley suffered a ligament sprain to his ankle during training on Tuesday and subsequently has been pulled out of the match against the Pumas this weekend," said Wales physiotherapist Mark Davies.
"He will remain in camp and his progress will be reviewed early next week before a final assessment is made.
"Morgan has a grade two tear to his hamstring and he will now be in recovery and rehab for a period of up to four weeks."
Wales round off their November international programme with next weekend's home Test against Australia and team management will make a decision over whether to call up any additional players early next week.
Revised Wales team to play Argentina at the Millennium Stadium here on Saturday (1430GMT):
James Hook; Leigh Halfpenny, Jamie Roberts, Jonathan Davies, Shane Williams; Stephen Jones, Gareth Cooper; Ryan Jones (capt), Martyn Williams, Andy Powell; Luke Charteris, Alun-Wyn Jones; Paul James, Matthew Rees, Gethin Jenkins
Source: AFP Global Edition