"I don't know whether it just comes to race or the way I am, my personality. I'm not too sure," he said.
"I had seen some racist comments."
"I've seen two other Kiwi-born players receive a huge welcome and then there's a few question marks over me," he said.
"I don't try and call it out. It's mainly on Twitter that I see these things. It's people that I follow fighting for me against these people and then it comes up on my timeline.
"I never go looking for it but when I come across it, it's a little bit disheartening."
In November, Halaholo took to Twitter to hit back at critics of his Wales selection.
"I sort of expected [criticism] because I'd already seen a build-up towards it," said Halaholo.
"There are some trolls out there that tag me, and there's no need.
"You can have your opinion but I don't need to have a notification of you talking about me in that way, saying I don't deserve to be here.
"I have nothing against the [residency] rule - if you are against the rule that's fine, I don't care, it's your opinion - but it's more like picking and choosing who they think deserve it."
Halaholo says it was tough to go from the high of making the Wales squad to suffer an injury days later.
"That's because you go from such a high - named in the squad on the Wednesday - and then on the Monday I am called in told my season's done. You've done your ACL - six months," he told the Scrum V Podcast.
"I had been really happy. I was looking back on the last three years on the work I've done and the family I've made here with the Blues supporters and I was looking to branch myself out to the rest of Wales and see what I can do, but it wasn't to be.
