PROVIDENCE, R.I. (AP) _ Defense attorneys this week get their chance to question the state's star witness in Claus von Bulow's retrial on charges he tried to murder his heiress wife.

Jurors so far have heard only the unchallenged charges of Maria Schrallhammer, the maid of von Bulow's heiress wife, Martha ''Sunny'' von Bulow.

Miss Schrallhammer, 62, is the state's lead-off witness in its attempt to prove that von Bulow twice tried to murder his wife by injecting her with insulin during the Christmas holidays of 1979 and 1980 at the family's Newport mansion.

In the first two days of testimony, the maid said von Bulow sat idly beside his moaning wife for nearly five hours as she lapsed into the first of two comas. Doctors say she will not recover from the second coma.

The state is to complete its questioning of Miss Schrallhammer when the trial in Superior Court resumes Monday, after having adjourned Friday.

She was the first person to become suspicious of the Danish aristocrat after his wife's first coma and helped spark the private investigation that led to his 1981 indictment.

Von Bulow was sentenced to 30 years in prison in 1982, but his two attempted-murder convictions were overturned by the Rhode Island Supreme Court last year on state constitutional grounds.

On Friday, Judge Corinne P. Grande denied a defense motion for a mistrial after Miss Schrallhammer testified that she found Mrs. von Bulow covered with blood in the bedroom of her Manhattan apartment on Dec. 1, 1980.

Miss Grande ordered the testimony stricken from the record, however, and instructed Assistant Attorney General Marc DeSisto to tell the jury that he ''in no way intended to suggest that Mr. von Bulow was responsible in any way'' for the incident.

The defense says the blood was caused by a massive aspirin overdose and had no connection to Mrs. von Bulow's comas.

Miss Schrallhammer said last week she found a black bag containing various vials and, later, insulin and a syringe which the state contends were the ''tools'' of the alleged attacks.

Her testimony was similar - and at many points identical - to her 1982 testimony that helped convict von Bulow.

The defense team has said little about legal strategy since the start of the retrial. But several months ago, a defense lawyer said new evidence centering on notes made by an investigator ''could blow the prosecution's argument completely out of the water.''

The new evidence comes from the notes of Richard Kuh, a former Manhattan district attorney hired by von Bulow's stepchildren in 1981 to investigate their mother's comas.

Miss Schrallhammer went to work for Mrs. von Bulow in 1958 in Germany when she was married to Prince Alfred ''Alfie'' von Auersperg, a titled but penniless Austrian. They divorced in 1965 and she married von Bulow the next year.

Miss Schrallhammer now works for Mrs. von Bulow's oldest daughter, Princess Annie-Laurie ''Ala'' von Auersperg Kneissl.