Three tomato (Solanum lycopersicum) cultivars [Walter LA3465 (heat-tolerant), Edkawi LA 2711 (unknown heat tolerance, salt-tolerant), and LA1310 (cherry tomato)] and wild species S. chilense were compared for changes in leaf proteomes after plants were subjected to 39C heat treatment for 7 days. In all the tomato cultivars, several proteins related to methionine metabolism, and Rubisco activase were suppressed by the heat treatment. In the wild species, Rubisco activase was not affected by the heat treatment. Most of the identified proteins were suppressed by heat treatment.