The visual loss with exercise in Multiple Sclerosis (MS) patients is well known since Uhthoff mentioned it in 1890. In this study we wanted to see how many of our patients were complaining about paroksismal visual deterioration and its relationship with optic neuritis. 125 patients with definite MS diagnosis to paser criter„ followed up about 3.5 years were evaluated. We designed the study in two steps. In the first step of the study; we examined how often and seriously our patients complained of paroksismal visual deterioration spontaneously by using the neurological examination records. The predisposing factors of 45 (36 %) complaining patients were taken into account. In the second step of the study, we designed a detailed form to search for Uhthoffs symptom and gave it to all of the 125 patients. The predisposing factors of 85 (68 %) complaining patients were also recorded. We saw that nearly 100 % of the first group and 75 % of the second group had an optic neuritis attack previously. There were some patients that complained from Uhthoff symptom spontaneously in past examinations but didn't mention paroksismal visual deterioration in the form. It's obvious that using only one of the methods is not enough, for finding the frequency of Uhthoffs symtom, the two methods must be used together. We want to (take attention) to the point that this paroksismal symptom is known very well but can't take part in our treatment strategies in MS sulliciently.