The Apple co-founder died last Wednesday at the age of 56.
The death certificate, released on Monday by the Santa Clara County Public Health Department, said Jobs had a metastatic pancreas neuroendocrine tumor for the past five years. It listed his immediate cause of death as respiratory arrest.
Jobs had been battling health issues for the last decade, including pancreatic cancer in 2004. He underwent a liver transplant in 2009 after taking a leave of absence for unspecified health problems, then he took another leave of absence in January.
He resigned in August, saying "I have always said if there ever came a day when I could no longer meet my duties and expectations as Apple's CEO, I would be the first to let you know. Unfortunately, that day has come."
He handed the CEO job over to his hand-picked successor, Tim Cook.
The Associated Press contributed to this report.