Simple Summary Pancreatic ductal adenocarcinoma (PDAC) has a very poor prognosis, partly because existing preclinical models do not accurately recreate the tumor microenvironment. This study explores the use of 3D bio-printing, a cutting-edge technology, to develop more realistic cancer models. By combining pancreatic cancer cells and cancer-associated fibroblasts in a hydrogel, we have focused our efforts on constructing a PDAC, resulting in viable, proliferating tumors with heterogeneous composition. The findings suggest that 3D bio-printing can produce tumor models that maintain cell viability and offer a versatile platform for improving cancer therapy research. Abstract Pancreatic ductal adenocarcinoma (PDAC) is a disease with a very poor prognosis, characterized by incidence rates very close to death rates. Despite the efforts of the scientific community, preclinical models that faithfully recreate the PDAC tumor microenvironment remain limited. Currently, the use of 3D bio-printing is an emerging and promising method for the development of cancer tumor models with reproducible heterogeneity and a precisely controlled structure. This study presents the development of a model using the extrusion 3D bio-printing technique. Initially, a model combining pancreatic cancer cells (Panc-1) and cancer-associated fibroblasts (CAFs) encapsulated in a sodium alginate and gelatin-based hydrogel to mimic the metastatic stage of PDAC was developed and comprehensively characterized. Subsequently, efforts were made to vascularize this model. This study demonstrates that the resulting tumors can maintain viability and proliferate, with cells self-organizing into aggregates with a heterogeneous composition. The utilization of 3D bio-printing in creating this tumor model opens avenues for reproducing tumor complexity in the future, offering a versatile platform for improving anti-cancer therapy models. Keywords: 3D bio-printing; pancreatic ductal adenocarcinoma; co-culture