Assessing long-term tumor survival rates is crucial for evaluating the effectiveness of tumor treatment and burden. However, timely assessment of long-term survival in patients with pancreatic cancer is lagging in China. In this study, we applied period analysis to estimate the long-term survival of pancreatic cancer patients using data from four population-based cancer registries in Taizhou city, eastern China. A total of 1121 patients diagnosed with pancreatic cancer between 2004 and 2018 were included. We assessed the 5-year relative survival (RS) using period analysis and further stratified by sex, age at diagnosis, and region. The 5-year RS during 2014–2018 overall reached 18.9% (14.7% for men and 23.3% for women, respectively). A decrease of the 5-year RS from 30.3% to 11.2% was observed in four diagnostic age gradients (< 55, 55–64, 65–74, and > 74 years age groups). The 5-year RS was higher in urban (24.2%) than in rural (17.4%) areas. Moreover, the 5-year RS of pancreatic cancer patients showed an overall increasing trend for the three periods (2004–2008, 2009–2013, and 2014–2018). Our study, using period analysis for the first time in China, provides the latest estimates of the survival of patients with pancreatic cancer, which provides essential evidence for the prevention and intervention of pancreatic cancer. The results also indicate the importance of further applications of the period analysis for more up-to-date and accurate survival estimates.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12885-023-11119-3.