||The communication industry is crucial to Thailand and has an impact on the world in all industries. Many communication companies bring advanced technology to disrupt the old era. Nowadays, more than 5.19 billion people have mobile phones, 68.37 percent of the world population. Furthermore, even mobile phone companies are leading the change to the world. On the other hand, the mobile network companies are the complementary industry of mobile phones. Mobile phones are hardware; the mobile network is vital to help the mobile work efficiently. In Thailand, the Telephone Organization of Thailand (TOT) and CAT Telecom Public Company Limited were two state enterprises that started the mobile carrier and held the rights to the bandwidth used for mobile communications. In 2005, The government allowed private companies to get the bandwidth license for the first time. In 2006, the Thai government allowed the foreigner to possess the percentage of shareholders from 25 percent maximum to 49 percent. Currently, there are big three companies as TRUE, AIS, and DTAC, in the industry. The market structure is an oligopoly market, and NBTC is the regulator to control the industry. However, to compete in the mobile network industry nowadays. There is not just competition only the signal strength, and the price. The mobile network carriers compete on a broad dimension to steal market share from competitors. Therefore, all mobile carriers have to develop service, privilege, variety of products, billing systems, digital services, streaming applications, and mobile contract to expand market share and increase customer loyalty. As Mr. Somchai Lertsutiwong, the CEO of AIS said “the company’s vision is that AIS needs to transform our company from a mobile operator to a digital life service provider” It could reflect that mobile network carriers have to adapt by providing digital services and content to survive.This research is a contemporary topic in applied marketing and the area of social issues and technology. This research aims to study the mobile operator industry in Thailand, including each carrier’s fundamental details on the supplier side and customer perception and behavior on the demand side. The findings will guide marketers in any industry to set a marketing strategy that are becoming more complicated nowadays. This study used exploratory research to gain an overview of the market industry and insights. Exploratory research included secondary research and in-depth interviews. Finally, a questionnaire was used, the Statistical Package Software for Social Science (SPSS) was employed for the statistical analysis.The survey was collected from 679 respondents; there were four types of segmentation: carrier, privilege & non-privileged, payment system, and two step-cluster analysis. The results indicate that each carrier’s average spending is not significantly different; however, the privileged customers spending higher than non-privileged customers, and postpaid system customers spending higher than prepaid system customers.The results reveal that customers are concerned about signal quality, signal coverage in the city, internet speed, branch service, and proper package, respectively. On the other hand, privileged customers are concerned about privilege factors significantly, and non-privilege customers are concerned about the price significantly. Prepaid customers are also concerned about the price, free Wi-Fi, branch service than postpaid customers significantly. In terms of customer satisfaction, AIS is the carrier with the highest customer satisfaction ratings. AIS could provide key factors such as signal quality, signal coverage in the city, internet speed, and proper package close to the customer expectation. In contrast, DTAC had the lowest satisfaction due to the lowest score in all factors except call center and online service.