An Upper West Side dog walker has been charged with stealing more than $50,000 from the elderly mother of one of his clients, the Manhattan district attorney’s office said yesterday.

The dog walker, Daniel Natale of Luna Dog Service, allegedly used a checkbook, credit cards, and a debit card to steal cash from his 84-year-old victim, for whom he occasionally ran errands, prosecutors said. The victim noticed the fraudulent activity after prosecutors say Mr. Natale had already withdrawn $36,618 from her Chase bank account using a debit card, and cashed checks totaling $14,660 from a Citibank account. He is also charged with taking out more than $3,000 using the victim’s credit card and adding himself as a joint holder on the account of another credit card.

The company sent him his own card, which he allegedly used to steal $3,018 out of her account.

The district attorney’s office did not identify the victim, but said she had met Mr. Natale through her daughter, who had been allowing him to live in an apartment she owned rent-free.

His business serves mostly residents living on the Upper East Side and Midtown, according to prosecutors. Mr. Natale did not return a phone message asking for comment.

On the Web site of his dog walking service, he has posted dozens of pictures of his clients’ dogs. The Web site is written in the first person as if by his own dog, Luna, an English sheep dog and Tibetan terrier mix.

“At first he was very nervous, but I assured him not to worry or be scared because I would teach him everything he’d need to know about taking the absolute best care of my friends,” the Web site says of Mr. Natale’s initial foray into the dog walking business.

“He has been in this business for over five years now and I can say proudly that he’s the best and nicest dog walker in NYC.”