The midfielder is ready to pledge his long-term future to the club.
Benayoun said: "West Ham is one of my favourite clubs and it's great to be here. Although it is only a loan, there is an option in January to extend it to the end of the season.
"My ambition is to be at the club for a full season and to make it a good one.
"There is strength in depth here. When I was here the first time we had a few talented players but this time we have a lot of quality - Mark Noble, Matt Jarvis, Kevin Nolan and Ricardo Vaz Te.
"I think we have a nice balance between attackers and defenders, which helped us to start with three clean sheets in four league games.
"If you can do that in the Premier League, it shows the strength of the team defensively and we have the talent offensively to score goals."