The Naval Academy midshipman accused of taking cocaine during a weekend leave said yesterday he will not resign from the academy and will present his case to the secretary of the Navy.

Navy officials, after three investigative hearings, gave academy senior Jeff Bellistri, 23, of Severna Park, Md., until 8 a.m. today to resign from the school.

But Bellistri said he will not resign because he is innocent.

"I never used cocaine, never. I'm not afraid to be judged on my credibility, on my record or my character," he said from his home. "I don't use drugs, and I never worried about the urinalysis program before because I believed I had nothing to fear.

"One test result, one reading from a machine, has now become judge and jury, and all the other evidence I presented is considered irrelevant."

On Nov. 12, 1985, Bellistri and approximately 100 other midshipmen were subjected to a random drug test. A week later, officials told Bellistri that his test showed evidence of cocaine use.

On Friday, Academy Superintendent Rear Adm. Charles Larson upheld a decision by the academy's commandant finding Bellistri guilty of drug use.

Academy spokesman Lt. Comdr. Stephen H. Clawson said Friday that Bellistri's urine sample was tested twice by a Navy laboratory in Norfolk and a third time by a private laboratory in Baltimore. Each test showed that a large dose of cocaine had been taken, he said.