Gaiserwald has a population (as of ) of . , about 12.1% of the population was made up of foreign nationals. Of the foreign population, (), 148 are from Germany, 113 are from Italy, 284 are from ex-Yugoslavia, 57 are from Austria, 90 are from Turkey, and 170 are from another country. Over the last 10 years the population has grown at a rate of 9.4%. Most of the population () speaks German (93.4%), with Serbo-Croatian being second most common ( 1.4%) and Albanian being third ( 0.9%). Of the Swiss national languages (), 7,003 speak German, 28 people speak French, 61 people speak Italian, and 10 people speak Romansh.