The present investigation is concerned with reflection and transmission of plane waves at an interface between two micropolar viscothermoelastic half spaces with different micropolarity and viscoelastic properties. The three-phase-lags theory of thermoelasticity developed by Roychoudhuri[12] is used to study the phenomena. The reflection and transmission coefficients of longitudinal displacement wave (LD-wave), thermal wave (T-wave) and two coupled transverse displacement and microrotational waves (CD-I wave and CD-II wave) have been derived for different incident waves. The amplitude ratios of different reflected and transmitted waves with angle of incidence are obtained for different theories of viscothermoelasticity i.e. three-phase-lags model, dual-phase-lags model and GN typeIII model. The Viscosity effect on the amplitude ratio are depicted graphically