Colchester Hospital has been under investigation since November 2013, when claims were made that data was changed to meet national guidelines.
Essex Police said it found "no criminal offences" had been committed.
The hospital said the news would be "enormously reassuring" to its cancer patients.
Dr Barbara Stuttle, director of nursing and quality at Colchester Hospital University NHS Foundation Trust, said: "The police investigation has been hanging over the trust for almost two years so it is pleasing that, at long last, we can finally draw a line under it.
"It is another important step towards rebuilding public trust and confidence in the cancer services we provide."
A report released in December said the inaccuracies had been down to managerial incompetence, rather than the purported bullying of staff highlighted by the Care Quality Commission (CQC) in 2013.
Staff had told inspectors they were "pressured or bullied" to change data relating to patients and their treatment to make it seem people were being treated in line with guidelines, the CQC said.
Ch Insp Tracy Hawkings said police had interviewed staff and carried out an independent assessment of medical records.
"Throughout the investigation we have worked with NHS England, the trust and other health organisations to ensure we had access to all the information, reports and medical data that could be provided," she said.
"We have concluded that no criminal offences have been committed and there is no evidence to support any criminal charges against either any individuals or the hospital trust."
A hospital placed in special measures over "inaccuracies" in its cancer waiting times did not commit any criminal offences, police say.