We introduced heat-assisted DLP technique to the 3D printing of geometrically complex PEG-based networks and the subsequent hydrogels after swelling. Using BAPO-conjugated 4-arm PEG as the photoinitiator, a series of PEG macromonomers with MW ranging from 2000 to 20 000 g mol -1 were printed by DLP at elevated temperature. The 3D printed PEG networks showed MW-dependent mechanical properties and high MW PEG (6000 -10,000 g mol -1 ) provided much higher mechanical strength and elastic modulus compared to commercial PEGDA (700 g mol -1 ). Thanks to the semicrystallinity of PEG polymers, 3D printed objects showed shape-memory behavior. After postprinting swelling, the corresponding hydrogels also showed MW-dependent elasticity, while the 4-arm polymeric photoinitiator resulted in higher strength of low MW PEG (700 -4000 g mol -1 ) hydrogels compared to that of the hydrogels using commercial BAPO. Importantly, a dual-macromonomer strategy allowed the 3D printing of mechanically tough hydrogels by combining high and low MW PEG macromonomers. Using this technique, tough cytocompatible hydrogels with bone-like structures were fabricated and seeded with cells for potential application in tissue engineering.