The purpose of this paper is to estimate CO2 emissions from Peru's domestic air transport and how much they would be reduced if the network, currently centered around Lima's airport, was organized differently. Results show that, in 2014, Peruvian domestic air transport was responsible for emitting approximately 657,446 MT of CO2. This is equivalent to US$4.7 million, US$60.33 per one-way flight or 8.7 cents per km. If only the less-polluting aircrafts were used, CO2 emissions would be reduced by 2.8%. If instead of having to use Lima's airport as a hub there were direct connections among the country's seven busiest airports, yearly emissions would be reduced by 3.8%. A large part of the savings in this scenario (45%) would come from eliminating LTO cycles. Both scenarios combined would save the environment 40,893 MT of CO2 per year (6.2%).