We present photoelectric and spectral observations of a hot candidate proto-planetary nebula early B-type supergiant with emission lines in spectrum-IRAS 19336-0400. The light and color curves display fast irregular brightness variations with maximum amplitudes {Detla}V=0.30m, {Detla}B=0.35m, {Detla}U=0.40m and color-brightness correlations. By the variability characteristics IRAS 19336-0400 appears similar to other hot proto-planetary nebulae