This research aims to 1) study Thai population compliance with doctrines, 2) study the good understandings among religions, and 3) study the practical application of doctrines. Thai population who are more than 13 years old is used as a sample group. 2,858 representatives of the 5 religions; Buddhism, Islam, Christianity, Brahmanism-Hinduism and Sikhism, from each region and a Bangkok district were selected. Therefore, the total number of people is 20,006 in the sample group. Questionnaire was used for collecting data while statistics used for data analysis were frequency, percentage, mean, standard deviation, F-test, and P-value. Research results show that (1) Doctrines compliance: It was found that in overall, 92.64% of the votaries comply with their doctrines. When considered by individual religions, all (100%) Brahman and Hindus and Sikhs comply with their doctrines, followed by 93.72% of Islamic, 93.26% of Christians, and 75.19% of Buddhists. (2) Good understanding among religions: It was found that in overall, 51.58% of the votaries well understand one another among their religions. Christians have the best understanding with 83.75%, followed by 58.11% of Islamic, 55.29% of Buddhists, 42.86% of Brahman and Hindus, and 17.86% of Sikhs. (3) Practical application of doctrines: It was found that in overall, 97.56% of the votaries practically apply their doctrines. The most are the Brahman and Hindus and Sikhs (100%), followed by 98.23% of Islamic, 97.55% of Christians, and 92.02% of Buddhists.(4) Comparison results of doctrines compliance, good understanding among religions, and its practical application show that various types of votaries have different doctrines compliance, good understanding among religions and its practical application with statistical significance at 0.05 level while different sex, age, education, region, and occupation have no difference with statistical significance at 0.05 level.