Asthma is an old and increasingly life-threatening disease. The mechanism of asthma is, however, not well understood. In asthma, the gas exchange as the primary function of the human lung can be seriously impaired. Since gas exchange is achieved through a series of respiratory acts that are operated via physical forces and stresses acting on each level of the lung structure, biomechanics of lung tissues including airway smooth muscle (ASM) must have an important role in asthma. In this article, we review latest advances in aspects associated with ASM biomechanics. We first discuss the mechanical environment in the lung structure, then introduce the latest findings of ASM structure and function including ASM contractile filament organization, functional length range and adaptation, cellular structure and functional changes in responses to mechanical perturbation, ASM tone as a mediator of strain-induced response, and a novel glassy cytoskeletal dynamics. These provide a multiscale view of the current understanding of ASM biomechanics, which may shed new light, and hopefully lead to a better approach in addressing fundamental issues in asthma phathophysiology.