The special 40th anniversary edition saw an unstable Carl King attempt to rape ex-fiancée Chas Dingle (Lucy Pargeter), who was forced to defend herself by hitting him over the head with a brick.
Ofcom has confirmed that it has received 18 complaints over the episode. The broadcasting regulator will now assess whether the scenes were suitable for the programme's 7pm timeslot.
An ITV spokesperson told Broadcast: "We are aware that there were a few complaints to Ofcom about the level of violence in the episode. The programme also got very many letters and emails praising it.
"We were very careful to keep the drama within acceptable bounds for pre-watershed scheduling, and the episode was preceded by a continuity announcement that some scenes might be upsetting."
Emmerdale Live was the highlight of the soap's 40th birthday celebrations, pulling in a peak audience of 9.15 million viewers on the night.
The episode saw actor Tom Lister's final scenes in the role of Carl, as his enemy Cameron Murray murdered him shortly after his altercation with Chas. Get the Inside Soap magazine on your iPhone or iPad