The group have promised to take their fight to the German Embassy in Bangkok to demand Alfred Gatt be deported immediately.
The dog reportedly attacked German man Mr Gatt and his Rottweiler while the pair were out on their daily walk.
Mr Gatt was fined B1,000 for the attack which was the maximum fine permitted under Thai Law, police say.
Mr Gatt, 65, is reportedly pursuing legal action against the owner of the Labrador, Chief Petty Officer First Class Gampon.
He is also requesting compensation of B300,000 for injuries he claims he sustained following multiple attacks by the Labrador.
Followers of a Facebook page called “A Call for Animal Rights Thailand” were told to gather in front of Mr Gatt’s house on Saturday.
The small group were clearly angry but remained non-violent. Police officers present appeared to side with the protesters and even posed for pictures with the protest group.
A small delegation of protesters were invited into Mr Gatt’s house to discuss the incident but they reportedly refused to go. Instead a Thai who speaks fluent German used foul language to entice Mr Gatt to confront the group in front of the many cameras which were documenting the protest.
Despite the placards which demanded Mr Gatt leave Thailand, he did appear for less than a minute in an attempt to defend himself but he was met by angry protesters and was forced back into the house. His wife, Vilawan, did her best to defend her husband by showing them pictures of injuries Mr Gatt sustained during the many attacks.
The protesters ignored the pictures and did eventually disperse after they were addressed by an emotional Petty Officer Gampon who thanked everyone for coming and confirmed how much he missed his pet dog.