Polymers as one of the fastest growing groups of widespread use of synthetic materials are characterized by a great diversity of structures. Structural characterization of polymers generally includes: an assessment of the average molecular weight (Mn) and the molar mass distribution (PD) to determine the structure of repeating units (mers) sequence analysis of the copolymer, identification of the end groups, the detection and identification of contaminants and substances present in the composition of the polymer asa dopant. Modern mass spectrometry (MS) offers the opportunity to study the smallest structural details of macromolecular materials [1–10]. Because of the variety of potential structures of polymer analysis process is to answer a few questions by a certain pattern. The first step is to determine the chemical structure of the polymer backbone. The second step is to identify whether the chains have branching points and define the degree of branching. The third important step is to correct end groups identification, also for the detection of cyclic oligomers that can be present. The structural studies can be made by mass spectrometer using reflectron mode. In the essence, the method involves three steps. The first analysis is performed with standard mass spectrum of the sample. Then the precursor ion (parent ion) is selected, which is subjected to further analysis by MS changed voltages and reflectron mode. This paper aims to present the issues related to the detailed analysis and characterization of polymeric materials produced on a large scale. Before, for materials such as poly(propylene), poly(ethylene), poly(styrene), polycarbonate, etc., increasing demands on the mechanical and technological parameters were placed. Maintaining a high level of products is associated with a very rigorous process control of the manufacturing, processing and transportation at every stage. The optimal tool for the structural characteristics of these polymeric materials is the defense technique MALDI-TOF MS (Matrix-Assisted Laser Desorption/Ionization Time- -Of-Flight Mass Spectrometer) due to its versatility, speed and extremely high precision. Below, we present some aspects of MALDI MS analysis of polymeric materials and composites. Note, that the following literature review focuses on the recent developments in the field of preparation of the samples, to achieve high mass resolution, the identification of polymers and copolymers, the accuracy of the molar mass determination and the identification of functional end groups, sequence analysis of the copolymer.