近年来发现和证实了许多新强子态，它们是多夸克态的最佳候选者。多夸克态吸引了大量的研究工作，成为国际研究热点。QCD求和规则是研究多夸克态的有力工具，目前广泛应用于粒子物理的各个研究领域。我们利用QCD求和规则，对隐粲、隐美紧致四夸克态、五夸克态、松散介子-介子型分子态、介子-重子型分子态、强子分子态以及混合态的质量谱和极点留数，做出统一而可靠的计算。同时，我们利用QCD求和规则系统而可靠地计算这些多夸克态的两体强衰变和辐射衰变中强子间的耦合常数，系统研究多夸克态的两体衰变宽度和两体衰变中的分支比，比较国际高能物理实验数据，用质量和宽度两个参数来确认新强子态，重新审视新强子态的确认。我们的研究工作旨在为国际高能物理实验提供可靠的理论依据，为我们认识多夸克态提供必要的理论基础，提高人们对QCD低能动力学的认识。

In recent years, many new hadron states have been observed and confirmed, they are excellent candidates for the multiquark states. The multiquark states have attracted a lot of research works and become an international hot subject. The QCD sum rules is a powerful tool in studying the multiquark states, and has been applied extensively in particle physics. We study the hidden-charm and hidden-bottom compact tetraquark states, pentaquark states, loose meson-meson type molecular states, meson-baryon type molecular states, hadromolecular states, and mixed states with the QCD sum rules in a systematic way, and make reliable predictions for the masses and pole residues. Moreover, we study the hadronic coupling constants of those multiquark states in the two-body strong decays and radiative decays with the QCD sum rules in a systematic way, and make reliable predictions for the decay widths and branching ratios. We use two parameters (the mass and the width) in assigning a new particle by comparing to the international high energy experimental data, and revisit the assignments of the new hadron states. We obtain reliable theoretical predictions to be confronted to the international high energy experimental data in the future, and make necessary contributions to the multiquark states and low energy dynamics of QCD.