The purpose of this research work was to analyze the behavior of the pandemic caused by the SARS-CoV-2 virus (COVID-19) in Peru, using the SIR epidemiological model. Using the data, from its inception on March 6, 2020, to June 10, 2020. In our case, in Peru, It has been forecast that the disease will peak, on the contagion curve, at 160-day from the first case. The total duration of the disease is approximately 15 months (450 days), the number of deceases will be approximately 1% of the entire population, and the total number of infected will reach approximately 85% of the population. The evolution of the parameters β, γ and μ show that the disease always tends to disappear, since they are directly related to the population and the condition of the individuals (Susceptible, Infected or Recovered). These parameters control the model, however, it is not trivial to be able to establish adequate values over time, since it will largely depend on the culture of the population mainly, and the policies that the government proposes, and in which way the population will comply with these policies to control the evolution of the pandemic. For example, one way to control the parameter β is compulsory social isolation with a strict epidemiological stratified fence by cities, thereby reducing the value of the contagion rate to zero and allowing the pandemic to be effectively controlled. However, in Peru, this control has not been achieved, since the population is very varied in its culture and quite reluctant to comply with the government's recommendations.