This book is designed as an advanced guide for experiments in Modern Physics. It covers many topics of practical statistics methods applied in Physics: measurement and uncertainties, error propagation method, statistical analysis and graphs, the least square method (regression analysis), Gaussian Distribution, Poisson Distribution, Error propagation and probable errors, Differential error analysis, Covariance ellipse, the method of the least squares in connection with the maximum likelihood, covariance ellipse and determination of the energy calibration-channel numbers (Kα energies), Moseley Law, etc. It is included the deduction of many formulas and statistical analysis in order to clear the concepts of the statistical methods applied in Physics. It is hoped that this book fills all needs of the students to get the fundaments of the statistical methods and to achieve the interest and motivation of the students for this topic.