The invention relates to an evaporative humidifier including a water reservoir, a wick unit and a fan unit. The wick unit is configured to absorb water from the water reservoir. The fan unit is arranged within a fan housing and configured to force an air flow to flow through the wick unit. The fan housing comprises a top cover unit defining at least one annular air outlet at an outer part adjacent a circumference of the top cover unit. One of the main advantages of this invention is that the evaporative humidifier has an optimal air flow path and can operate in a low noise. The invention also relates to an indoor climate controlling system using such an evaporative humidifier.