The present study was conducted on different supplemented gliotoxin growth medium by using some chemical inducers (micronutrients mixture, potassium tartrate and thiamine) to improve antagonism, crude extracts and volatile compounds activities of T. harzianum against R. solani. T. harzianum grown on medium supplemented with potassium tartrate decreased the mycelial growth of R. solani by 89% compared with T. harzianum alone (63.3%). Also, exhibited the significantly higher activity of the crude extract and the volatile compounds. The micronutrients followed by the thiamine addition recorded the highest activity of the secondary metabolite. Treated Trichoderma enhanced bioactivity against the pathogen when transferred on PDA medium without addition of the tested materials. Light microscope observation revealed that malformed and damaged pathogen hyphae occurred more clearly after contact with the treated T. harzianum. The GC-MS analysis showed detection of antifungal compounds as 2,3-butanediol, Decane, 2,4,6-trimethyl-, phenylethyl alcohol, acetic acid, 1 H-Benzocyclohepten-7-ol,2,3,4,4a,5,6,7,8-octahydro-1,1,4a,7-tetramethyl-,cis- in the crude extract of Trichoderma grown on medium supplemented with different tested compounds. Soaking faba bean seeds Giza 429 in treated Trichoderma suspension before sowing in infested soil increased survival faba bean seedlings compared with the untreated Trichoderma. As a result, the tested chemicals improved the antagonistic activity of T. harzianum and can be used as biological fungicides.