Measles is a contagious disease that can be prevented by vaccination. In this infection, cellular response and antibody response are important. In case of cellular immunodeficiency the disease can lead a severe course. In this paper, we presented a case of measles in which an adequate antibody response occurred weeks after the onset of infection in an individual with a healthy immune system. A 21-year-old male soldier who was admitted to hospital with high fever, coryza, rash and headache that started four days ago was hospitalized with an initial diagnosis of measles, and serological tests for measles were IgG positive and IgM negative (just below the borderline value). A sudden elevation was observed in IgG index values after one-week later. Measles IgM became positive after two weeks and the elevation in IgG values were helpful with the diagnosis. In cases where IgM response is not positive in expected period, marked elevation in IgG index values and direct diagnostic tests such as measles RNA in the upper respiratory tract samples and urine will be useful.