Climate change is a great challenge and a prime factor limiting seed production, which is considered an integral part of food security for providing consumed yields. The experimental layout was split plot in completely randomized block design[DAEH1]  with four replicates. In 2021 and 2022, the experiments were  performed under high and low-temperature stress conditions during the four growing seasons of winter and summer. The three treatments, i.e., calcium boron (Ca + B), salicylic acid (SA), and humic acid (HA) were used to mitigate the adverse effects of low and high-temperature stress on the cucumber seed set. All treatments showed an improvement in seed development. The treatments increased the activity of antioxidant enzymes peroxidase (POD, EC 1.11.1.7), superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11. 1.6), plant hormones, brassinosteroid (BRs) and ethylene in cucumber plants during seed formation stage.  The study showed that the increase in the activity of antioxidant enzymes and plant hormones concentrations had an efficient role in mitigating adverse effects of temperature on seed quantity, and nutritional elements. Furthermore, add Ca + B the most improved fruit length, fruit weight, fruit diameter, seed quantity, seed quality, germination percentage, and rate, under high-temperature condition. All treatments increased the expression levels of 9 temperature stress-related genes compared with control. Ca + B application the most induced the expression of CsGy2G003240 gene (serine/threonine-protein kinase Nek2-like isoform X1).  Overall, Ca + B variant best of all improved the physiological, biochemical, and molecular response of cucumber plants during the seed formation.