Christopher Britt, of Wheeldon Close, Ilkeston appeared at Derby Magistrates Court after being arrested in an Ilkeston high Street.
Derbyshire police were called to Bath Street on March 11 following reports that a man was attacking a dog by throwing it up into the air and punching it.
The force said: "Officers arrested Britt at the scene and seized the Staffordshire bull terrier."
The 31-year-old made threats to the officers during the incident.
Britt appeared before magistrates in Derby on Tuesday, May 3 and pleaded guilty to causing unnecessary suffering to an animal under the 2006 Animal Welfare Act. He also admitted using threatening or abusive words with the intent to cause fear of violence.
He was fined a total of Â£200 and ordered to pay Â£651 costs. The dog has been rehomed, added police.