The unwise application of synthetic chemical pesticides, commonly used to control plant diseases, can result in environmental pollution, crop contamination, and human health risks. Hence, biological control agents offer an alternative for managing plant diseases, and one such agent is Trichoderma sp. This study focuses on the isolation and identification of Trichoderma sp. that produces Indole Acetic Acid (IAA) from the rhizosphere of organic rice fields. The rice varieties studied include IR64 white rice, Mentik Wangi red rice, and Cempo black rice, cultivated using conventional planting methods in the Wonogiri region. The identification process involved assessing morphological macroscopic characteristics such as colony color, colony shape, growth direction, and surface features. Microscopic identification was carried out using a binocular microscope to examine conidia, conidiophores, and phialides. The research identified five Trichoderma species in the organic rice fields. These were classified as follows: M1 as T. harzianum, M2 as T. asperellum, P1 as T. inhamatum, H1 as T. harzianum, and H2 as T. atroviride. All isolates displayed hyaline hyphae. At the microscopic level, all isolates exhibited conidiophores developed in upright cushion-like structures, with light green conidia having smooth walls, an oval and branched shape, and a vertical arrangement. However, each isolate demonstrated distinct branching and phialide shapes. Quantitative analysis revealed that IAA concentration measurements were in direct proportion to qualitative IAA assessments. In qualitative tests, distinct color changes to deep pink were observed. Notably, isolate M2 exhibited the highest IAA concentration, whereas isolate H1, which displayed a deep yellow color change, had a lower IAA concentration..