Problem statement: At present, Thai society widely assimilates culture, beliefs and rites concerning deities of Buddhism and Hindu-Brahmanism by worshipping the deity images at the temples or the abodes of gods in Bangkok and circumferences. A typical worship is to pray the deity for help. As a matter of fact, people should help themselves first and use a prayer as willpower. The purpose of this research were these; (1) to investigate the background of culture, belief and rites concerning deities of Buddhism and Hindu-Brahmanism in Bangkok and circumferences, (2) to investigate the current situations of the assimilation of culture, beliefs and rites concerning deities of Buddhism and Hindu-Brahmanism in Bangkok and circumferences and (3) to determine a suitable assimilation model of culture beliefs and rite concerning deities of Buddhism and Hindu-Brahmanism for peace of Thai society in Bangkok and circumferences. Approach: A qualitative research was used for this research. Research areas were these: (1) Yannawa Temple, Yannawa sub district, Sathon district, Bangkok, (2) Lum Charoen Satta Temple, Yannawa sub district, Sathon district, Bangkok, (3) Brahma House at the Erawan Hotel, Lum Phini sub district, Pathumwan district , Bangkok, (4) Phai Lom Temple, Phra Pathom Chedi, Muang district, Nakhon Pathom Province, (5) Sisa Thong Temple, Sisa Thong sub district, Nakhon Chaisi, Nakhon Pathom Province, (6) Phra Sri Maha Uma Thewi Temple, Silom sub district, Bangkok district, Bangkok, (7) Visanu temple, Thung Wat Don sub district, Sathon district, Bangkok, (8) Thep Nimit Temple, Khok Phaed sub district, Nong Chok district, Bangkok, (9) Brahman Temple, Sao Chingcha sub district, Phra Nakhon district, Bangkok and (10) Ganesha House at Ratchada crossroads, Huay Khwang district, Bangkok. Deity worships have been held at these areas for a long time and a lot of people have participated in these worships. A population was the people who lived in 9 districts. A sample was selected by means of a purposive sampling, consisted of 16 key informants, 64 casual informants and 20 general informants. Research instruments were a survey, an observation, an interview, a focus group interview and a workshop. Research data were examined by means of a triangulation technique. Research results were presented by means of a descriptive analysis. Results: (1) Ancient-Thai society believed in deities and supernatural power so culture, beliefs and rites concerning deities have been handed down from generation to generation (2) At present, Thai people in research areas assimilate beliefs in Buddhist deities and Hindu-Brahman deities together, they worship both Buddhist and Hindu- Brahman deities; for example Bodhisattva, Ganesha, Brahma and Vishnu (3) A suitable assimilation model of culture, beliefs and rites concerning deities of Buddhism and Hindu- Brahmanism should consist of faith and wisdom by using beliefs and rites as the reinforcement of life and applying deity's virtue such as a virtue of do not make a sin throughout lifetime in order to enhance peace in society. Conclusion/Recommendation: Research result revealed a suitable assimilation model of culture, beliefs and rites concerning deities of Buddhism and Hindu- Brahmanism for Peace of Thai society in Bangkok and circumferences. This model can apply to enhance peace for other critical areas in Thailand.