Over 41 years of Lunar Laser Ranging (LLR) provide a unique data set of distance measurements between Earth and Moon with ever increasing precision. A further step on the way to mm-accurate LLR analysis is refined modelling such as that of the gravitational effect from mass multipole moments of Earth and Moon on the lunar orbit and orientation. The previous multipole expansion used at the Institut für Erdmessung has now been extended to higher degrees. The corresponding geocenter-reflector ranges are used for the comparison of the different models. For mm-accurate analysis, the complete gravity field up to degree and order 5 for the Moon and up to degree and order 4 for the Earth should be considered. For the optimal combination of the LLR data, a variance component estimation with respect to the observatories was tested and the new estimation of two relativistic parameters (equivalence principle parameter and variation of the gravitational constant) was carried out.
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