The relationship between Subjective well-being (SWB) and other factors is complex. However, few studies have reported a complex relationship between SWB and other factors across domains. We aimed to explore and clarify the one-to-many relationships between SWB and various factors among Japanese adults aged 20-85 years, using graphical modeling and data from the Iwaki Health Promotion Project (IHPP). An undirected graph that included factors such as nutrient intake, eating behavior, mental and physical health, social situations, and SWB was created using data from 519 participants in the IHPP of 2021. The graph indicated that four variables such as "CES-D", "Enjoying the taste of foods", "Health considerations" and "Household financial stability" were directly related to SWB. Additionally, we divided the participants into subgroups based on gender, age, employment status, educational background, and marital status and performed modeling to evaluate the differences in the structure of the SWB based on these attributes. Each graph indicated that the variables directly linked to SWB differed for each subgroup. Therefore, the mechanisms of SWB differed depending on people's backgrounds. We believe that these findings will be useful in proposing policies for improving the SWB of the Japanese people.