The 2^nd section of Bosque de Chapultepec was created in the 1960’s, and it is part of this important urban green area of the Metropolitan Zone of Mexico City. The 1^st and 2^nd sections of Chapultepec receives thousands of persons every week because of its extensive tree covered surface as well as the cultural and recreational facilities located in the area. Despite the dimension and importance of the 2^nd section, no tree inventories and diagnostics were done until 2007, and besides the section lack of a master plan to manage the tree cover. In 2012 the complete tree inventory of the section was renewed and was complemented with a diagnostic and characterization of the area. Trees were determined at species level, numbered, geolocated and the sanitary and structure conditions were evaluated. The data for the diagnostic was gathered by a systematic method by means of sampling stations located in an orthogonal shape every 100 m. The conditions of the section were evaluated and soil and foliage samples were collected. More than 27,000 trees were inventoried and the most frequent species were Fraxinus uhdei, Ligustrum lucidum, and Eucalyptus camaldulensis, which make up to 63% of the population; although 118 species were registered. Non important sanitary problems were detected in trees, but their structure was commonly bad or regular. The most frequent problems detected were soil compaction, lack of maintenance in green areas and infrastructure, and prune and fell down of trees in some areas.