Statement of Purpose: Chronic lung diseases are one of the major health problems that cause death and disability. Approximately 65 million people suffer from chronic lung diseases, and the number of patients is predicted to increase worldwide 1 . Lung transplantation is the only available treatment option for patients at end-stage disease. However, there is a chronic shortage of donor organs, resulting in a large unmet clinical need. To tackle this issue, the concept of transplantable bioengineered lungs has been proposed as a solution which might help to meet current transplantation needs 2 One of the ways to potentially build complex lung structure is 3D bioprinting, but bioinks which are compatible with 3D printers, support cell growth, and can maintain appropriate mechanical stability are unknown. In this regard, decellularized extracellular matrix (dECM) based materials are considered as a potential novel source of material for bioinks because they have been shown in other contexts to provide a suitable microenvironment for regeneration. However, there has been no investigation of their use in 3D printing of complex shapes. In this study, we evaluated the rheological properties of porcine lungderived dECM solutions and hydrogels to assess their suitability for 3D printing and to determine parameters which can be used to produce stable structures