Mueang Chaem was created in 1908, consisting of the tambons Mae Thap, Tha Pha, Chang Khoeng, and Mae Suek split off from Chom Thong. In 1917 it was renamed Chang Khoeng, as the district office was in that tambon. In 1938 it was reduced to a minor district and was subordinate to Chom Thong District. In 1939 it was renamed Mae Chaem. In 1956 it was upgraded to a full district. In 2009 the northern part of the district was split off to form the new district, Galyani Vadhana.
The district is a major producer of maize. Some 170,000 rai of the district are devoted to corn cultivation. Another 50,000 rai are planted in rice. Mae Chaem's reliance on corn monoculture has created three problems: farmers are heavily indebted due to the cost of corn crop inputs ; corn waste totals 90,000 tonnes per year. Half the waste is reprocessed as fertiliser, wood pellets, and animal feed, but the other half is burned in the open, contributing to Chiang Mai's spring air pollution; finally, due to the district's high elevation upstream of the Ping River, sediment from soil erosion has drifted down 272 kilometres to Bhumibol Dam— Thailand's largest hydroelectric power plant—shortening its lifespan. This last issue in particular has prompted the Electricity Generating Authority of Thailand, to create a program called "Energy for All". It envisions community-owned power generation from renewable resources. In Mae Chaem, the power project plans to use corn waste. EGAT has identified two district sites for the first-phase power plants. Each will have a capacity of one megawatt each. The two power plants will cost roughly 120 million baht each, with the initial electricity to be generated by 2022. Besides ending the open burning of corn residues, the project will provide power to the 70 Mae Chaem villages that have no electricity as of 2019. To eliminate soil erosion, corn monoculture is to be abandoned. The Energy Ministry will help locals to grow other plants such as giant acacia and bamboo to serve as biomass for the power plants.
Administration
The district is divided into seven sub-districts, which are further subdivided into 85 villages. Mae Chaem also has sub-district municipality status and covers parts of tambon Chang Khoeng. There are a further seven tambon administrative organizations. Missing numbers belong to the sub-districts which became Galyani Vadhana District in 2009.
