There is an old problem-the contradiction between microscopic and macroscopic experimental data for Prompt Fission Neutron Spectra for 235U at thermal energy. As a rule this difference was explained due to experimental uncertainties for microscopic (differential) experiments. In this paper I discuss the possible explanation of this contradiction due to strong energy-angular dependence of fission neutrons emission relative to fission fragment direction and its possible influence on macroscopic experimental results.