A procedure, based on analytical formulations, and antenna pattern cuts in different planes, is introduced for evaluating and analyzing the mobile antenna effective gain (Ge ) in multipath propagation environments. First, analytical expressions, which are relevant for numerical calculations of Ge, are derived. Then, different multipath propagation environments are modeled using statistical distributions for angular density functions of the randomly incident waves. The proposed procedure is finally applied to evaluate the mean effective gain (MEG) of the reference λ/2 and short dipole antennas in different mobile environments. Also, an inverted-L mobile handheld antenna is properly designed for GSM900 cellular system, and its MEG characteristics are investigated graphically using different co-polar and cross-polar antenna pattern cuts in different planes.