CYANOBACTERIA are a diverse group of prokaryotes which occupies many environments. In terrestrial habitats, they were famed to benefit both soil and plants through releasing bioactive substances of various biological functions. In the present study four treatments of Anabaena variabilis (seeds primed in 1% fresh cyanobacterial extract, seeds sown in soils inoculated with 3g fresh or dry cyanobacterial cells per 1 kg soil and wet seeds primed with 3g dry cyanobacterial powder per 1 kg seeds) were examined for their effect on Hordeum vulgare and Trigonella foenum-graecum L. plants. All treatments increased the germination percentage, shoot length, fresh and dry weights. The photosynthetic pigments, proteins, glutamic-oxaloacetic and glutamic-pyruvic transaminases (GOT and GPT) activities were also markedly increased specially in seeds primed with cyanobacterium dried cells. The protein profile of Hordeum vulgare seedlings revealed the appearance of newly formed protein band with molecular weight of 220 KDa in response to soaking the seeds in fresh cells extract. On the other hand, the protein profile of Trigonella foenum-graecum L. shows the induction of low molecular weight protein bands 10-14 KDa with all treatments. The plant growth promotive effect was attributed to the bioactive materials like phytohormones, exopolysaccharides, nitrogen, phosphorus and potassium estimated in the cyanobacterial biomass. The results recommended bio-priming the seeds of the two examined plants in dried cyanobacterial biomass as an economical and safe route fertilizer.