Aptamers are oligonucleotide ligands of synthetic single-stranded DNA/RNAs (ssDNA/RNA) with specific conformations which were created by in-vitro selection from a large random sequence pool, based on the affinity between oligonucleotides and the specific target molecules. This screening method is called Systematic Evolution of Ligands by Exponential Enrichment (SELEX). Aptamers' unique characteristics in protein binding have made them highly valuable tools for different diagnostic applications, downstream purification processes, analysis, new drug development and drug delivery. One of the important and valuable therapeutic plasma proteins is human coagulation Factor VIII (FVIII). In this investigation, FVIII was prepared from plasma source or recombinant production media and considered as a model protein for designing and development of relevant oligonucleotide aptamers. As the first step, random oligonucleotide library and its specific primers were designed and then chemically synthesized. After induction of 3D conformation by a specific temperature treatment, the random library was incubated with plasma derived FVIII. Gel filtration method was then employed as a partitioning step. During SELEX process, for the elimination of nonspecific cross interactions by other plasma proteins, two steps of negative selections were run. Finally, SELEX process was stopped when no more increase in the affinity constant (Kd) was observed and therefore the enriched pool was cloned. As the final step, protein affinity of enriched pools was determined using fluorescence method. It was found that the calculated Kd for enriched pools were 0.5 to 60nM and that they are comparable to the other specific ligands of the target protein.