Agriculture sensors play an important role in modern agriculture. The use of sensors in various agriculture sectors minimizes the environmental impact on crops, helps in increasing yield and saving cost of operation. Among all agriculture industries in Malaysia, the mushroom industry is a comparatively new and small. As most of the mushroom farms in Malaysia are small-scaled, their production capability is limited by inadequate environmental control system and the lack offinancial resources to upgrade the systems. This paper presents an environmental monitoring and controlling system to monitor and control the environmental conditions in a mushroom farm. It enables user to monitor temperature, humidity, carbon dioxide concentration and light intensity in a mushroom farm on an android device by using ThingSpeak online platform. The control algorithm is able to control devices in a mushroom farm automatically based on feedbackfrom the sensors to maintain the environment in an optimum condition for mushroom growth. The measured percentage error of temperature, humidity, carbon dioxide and the light using the developed system was as low as 0.4%, 1.5%, 2.2% and 1.34% respectively