The first example of a chemically crosslinked synthetic non‐ionic hydrogel showing reversible positive swelling behavior in pure water as well as electrolyte solution is highlighted. Homopolymeric hydrogels are synthesized from N‐acryloylglycinamide with N,N′‐methylenbis(acrylamide) as a chemical crosslinker via free radical polymerization in dimethyl sulfoxide (DMSO). The swelling‐ratio dependency of the hydrogels upon temperature as well as on the amounts of crosslinker from 1 to 4.8 mol% is studied. With 1 mol% crosslinker, the hydrogel is able to take up over three times water of its weight at 37 °C in pure water and phosphate‐buffered saline. All the samples show almost 100% of reversibility for at least 6 d up to 37 °C irrespective of the amount of the crosslinker, making them promising candidates for biomedical applications. The sample with a higher amount of crosslinker, i.e., 4.8 mol% is even stable for over 6 d at 70 °C. The first example of a chemically crosslinked synthetic non‐ionic thermophilic hydrogel is reported, showing positive swelling behavior in pure water as well as electrolyte solution. The swelling ratio dependency upon temperature as well as on the amount of crosslinker is studied. All the samples show almost 100% swelling reversibility with temperature between 4 and 37 °C for at least 6 d.