The alleged attacker was quickly ushered away by the PM's security and in the process, a 70-year-old woman at the function, was knocked to the ground.
No injuries were reported.
NSW Police Force said the 24-year-old alleged egger was arrested and taken to Albury police station where she was later charged with common assault and possession of a prohibited drug.
Police allege they found cannabis on the woman during a search at the police station.
She was bailed and will face Albury Local Court on 27 May.
The older woman knocked to the ground during the alleged egging, Margaret Baxter, later told ABC News she had recently had surgery but was feeling "fine".
"My main concern was I recently had surgery on my stomach so my main concern was holding my stomach to make sure it didn't get hit or somebody land on it," she said.
Ms Baxter said she was thankful for the assistance of Mr Morrison, who promptly helped her up from the ground.
"My concern about today’s incident in Albury was for the older lady who was knocked off her feet. I helped her up and gave her a hug. Our farmers have to put up with these same idiots who are invading their farms and their homes," Mr Morrison Tweeted shortly after the attack.
"We will stand up to thuggery whether it’s these cowardly activists who have no respect for anyone, or militant unionists standing over small businesses and their employees on work sites."
Mr Morrison later tried to make light of the attempt to egg him.
"There was one individual who came along today, who I think the CWA could give a really good idea about what you're supposed to do with an egg," the prime minister said.
Secretary of the Australian Council of Trade Unions Sally McManus slammed Mr Morrison's reference to unionists, stating that they "would never support such behaviour".
"How dare you accuse us of this and make the association. You seem to have no respect for the truth or any concern about running down your fellow Australians," Ms McManus wrote on Twitter.
Outside the venue, the alleged attacker told reporters she didn't mean to knock the other woman down.
"I don't want to give a report, no thank you. I've got to go to work. No comment," she said.
The CWA confirmed that the alleged attacker was not one of their members.
Following the incident, Opposition Leader Bill Shorten told reporters that it was "appalling and disgraceful behaviour".
"In Australia, we have violence-free elections. People are allowed to protest peacefully but anything approaching violence is unacceptable," he said.
"If this protester thinks she will get sympathy or support from me she couldn't be more wrong."
It's the second time in two months that a politician has been egged in public.
In March, far-right independent Senator Fraser Anning was egged by a 17-year-old boy at an event in Melbourne.
In response, Senator Anning, 69, tried to punch the young man before he was pushed to the ground. Both the Senator and 17-year-old Will Connolly avoided charges over the incident.