Three of the victims, aged between 20 and 50 years, were described as seriously injured in the attack which saw police marksmen called in.
The attack happened when two dogs escaped from a garden and ran amok in the road, first attacking one man and then another.
Police said that for a time paramedics had to stand off from the scene, leaving the injured lying in the road and on the pavement while officers tried to corale the second animal.
One was eventually forced into a dog crate by a householder and the other was captured by police. Neither animal had to be put down.
Police later arrested the 22-year-old owner of the dogs and he was taken to police cells where he was expected to be questioned later today.
A spokesman for Sussex Police said that police were called to Marline Road, St. Leonards-on-Sea, near Hastings, shortly before 9pm last night following a report that two dogs had escaped in to the street and several people had been attacked.
"When officers arrived one of the dogs had already been detained in a dog crate by members of the public.
"The second dog was quickly contained by a police dog unit, assisted by other police officers at the scene, in a garden, allowing South East Coast Ambulance Service to treat those who had been injured," said the spokesman.
"A 22-year-old local man was arrested at the scene on suspicion of allowing dogs to be dangerously out of control. He remains in police custody.
"It is believed that three people received serious but not life-threatening, injuries in the attack with at least five others receiving hospital treatment for minor injuries.
"Those who are seriously injured received bites to their bodies. All the injured people were aged between 20 and 50. None of the injured people are children.
"The two dogs have been taken into police custody. It is not known at this stage what breed the dogs are."
Inspector Sarah Godley said: "This was an incredibly distressing incident for everyone involved and quick work from members of the public and officers at the scene meant that the incident was quickly brought under control.
"Firearms officers were deployed to the incident but they were stood down when it became clear that the unarmed officers were able to get the dogs under control safely.
"We are now trying to establish exactly what has happened tonight and are keen to speak to anyone who witnessed the incident.
"Officers remain in the area and I would encourage anyone with information or concerns to speak to them."