Operations research is the optimal allocation of resources. The purpose of operations research is to provide logical bases for decision-making by searching for understanding and establishing complex conditions and using this understanding to predict system behavior and improve system performance. This article shows that operations research techniques play an important role in the financial market. To succeed in the stock market, it is necessary to be able to analyze this market with the help of methods. The purpose of this article is to find the application of operational research in the field of financial market analysis. It shows the topic of stock portfolio optimization considering the Markowitz model and value at risk. According to the Markowitz model, risk is related to return fluctuations, and the fluctuations are measured by return variance. The capital market article is a bridge that transfers the savings of economic units with surplus resources to investment units that need it. Using the capital market to finance government expenditures is one of the most common forms of financial transactions. Based on this, the capital market is considered one of the main players of financial provision in the economy of every country. Iran's capital market also started its development process in 1384 with a considerable speed and in the past decade, various financial institutions were formed in the process of financial provision through the aforementioned market. And its scatter has not been designed and compiled in the form of a coherent model.