In this paper, we apply a transition model to the data-set on stomach cancer mortality in Japan for the period 1955-2000. The data had been collected as a table of age- and period- specific mortality data at the Japanese Ministry of Health and Welfare. (http://wwwdbtk.mhlw.go.jp/toukei/index.html) An age-period-cohort model is often used to analyze cancer mortality data. However, that model is non-identifiable due to over parameterization. Applying a transition model to these data overcomes that problem. We propose a prediction method based on a transition model.