A south-east NSW country town known for its sea of rainbow flags has been subject to a spate of homophobic graffiti just days after Australia voted yes to same-sex marriage.

During the peak of the same-sex marriage campaign, Cobargo post office licensees Kyle Moser and David Wilson made headlines when Australia Post ordered them to take down a rainbow flag they were flying outside their post office.

Overnight, the Cobargo post office was graffitied with red spray-paint spelling out "say no to filthy homo".

The messages were sprayed on signs and power poles at the north end of the town. ( ABC News: Bianca Gurra )

Several signs and power poles throughout the north end of the town were also vandalised.

Post office licensee David Wilson said he did not initially register what had happened.

"[I was] horrified," he said.

"The community was more outraged than I was and they instantly went to the local hardware (store) to see what they could get to remove it.

A number of signs and power poles have been vandalised at Cobargo in the Bega Valley. ( ABC News: Bianca Gurra )

"Instantly, everyone was just horrified (and) disgusted and wanted to clean it off. So we got rags, we got WD40, we got paint thinner and it came off reasonably easy.

"There were local kids and there were some people new to town, just passing through, that were in their late 80s who stopped and helped too.

"It was a great outpouring of how good people can be."

Cobargo community shows support

Post office customer and Cobargo resident of 26 years Nikki Hutteman believed the issue was a result of fear.

Kyle Moser and David Wilson took over the Cobargo Post Office license two years ago. ( ABC South East NSW: Vanessa Milton )

"I actually felt violated myself," she said.

"This village is the greatest example of how love and positive thinking, and allowing that to rule, can outshine anything else.

"They [Mr Moser and Mr Wilson] are the most generous, good-hearted, wonderful human beings."

Other local residents have stopped by the post office to give Mr Moser and Mr Wilson their support and gifts.

The rainbow flag was removed from the post office after a customer complaint. ( ABC South East NSW: Vanessa Milton )

Rainbow flag torn down a week earlier

Former ACT Legislative Assembly member David Rugendyke, who lives at a property on the northern end of the town, said he had his rainbow flag ripped down from his flag pole.

"About a week ago some creep stole it (the flag) off the flagpole here … probably the same grub that graffitied the town," he said.

Mr Rugendyke said he was one of the community members who helped clean the graffiti off the post office.

"It was the necessary thing to do because once you leave graffiti up it just continues to grow," he said.

Mr Wilson and Mr Moser say they have contacted NSW Police who are investigating the incident.