Multiwavelength research of the cyclic variability of symbiotic nova RT Ser

For symbiotic nova RT Ser, we corrected the orbital period by using the analysis of long-term wave-like variability in B passband, the new value is 4431(±22) days. When analyzing the observations in the V-band, the cycles of the variability of about 93-107 and 159 days were found, which are probably caused by the multiperiodic pulsation variability of a red giant.