The performance of a solar air heater operating in conjunction with a pulsating heat pipe (PHP) is investigated experimentally in this study. This research focuses on the climatic conditions of the Semnan(35° 35′ N, 53° 25′ E) region in Iran. Pulsating heat pipes (PHP) are high-efficiency heat transfer devices, in which a combination of events and mechanisms occur and do not require any external force. The device fabricated for this study includes three main sections: flat collector , pulsating heat pipe and heat exchanger. The evaporator of the PHP is located inside the flat collector, while the condenser is inside the heat exchanger. The PHP is fabricated using a copper pipe with an internal diameter of 2 mm, and consists of 21 turns with charging ratio of 65%. the effects of local time is investigated for three month. Results show that while solar radiation increased, the performance of solar air heater increased too.