In the present study, we have isolated endophytic fungi Gliocladium cibotii from Verbena officinalis L. and tested against Oryza sativa L. seedlings for growth promotion. The strain was used to help Glycine max L. and Helianthus annuus L. under thermal stress. Association of G. cibotii with G. max and H. annuus enhanced chlorophyll contents, total biomass and plant height. Also, G. cibotii significantly curtailed lipids peroxidation and ROS (reactive oxygen species) in host species exposed to heat stress (40ºC). Furthermore, the concentration of ROS-degrading enzymes, like ascorbic acid oxidase (AAO), catalase (CAT), glutathione reductase (GR), peroxidase (POD) and superoxide dismutase (SOD) were boosted in test crops, while concentration of proline and ABA were inhibited. The phenolics and nutritional value (total lipids, proteins and sugars) of experimental plants were also enhanced. The results conclude that G. cibotii can be used as a heat stress mitigating weapon for food crops in the future.