Using the microclimate data of inside and outside greenhouse in Dawa of Liaoning Province from April 2012 to May 2013, this paper analyzed the characteristics of microclimate and temperature and humidity effects of inside and outside greenhouse under different weather conditions. The results showed that the maximum temperatures inside greenhouse on sunny, cloudy, overcast and rainy days were 28.9-29.6, 23.8-27.5, 14.6-22.9 and 10.3-21.4 ℃, being 5.5-33.5 ℃ higher than that of outside. Under the abovementioned weather conditions, the minimum temperatures inside greenhouse were 5.3-9.0, 6.8-9.9, 5.8-11.0 and 4.0-7.9 ℃, respectively, being 2.5-20.8 ℃ higher than that of outside, and the minimum humidity  inside greenhouse were 44.8%-67.7%, 59.4%-78.3%, 74.7%-91.8% and 82.4%-99.9%, respectively, being 0.8%-27.1% higher than that of outside, while the maximum humidity inside was slightly higher or equal to outside. The temperature difference between inside and outside greenhouse was larger at daytime, especially around noon, but smaller at nighttime. The humidity difference was lager at night, less or no difference at daytime. The warmer and wetter effects were more often observed on sunny days than under other weather conditions and in winter than in autumn and spring. The total solar radiation was 0 W·m^-2 before sunrise and after sunset, and the maximum value appeared around noon.