Abstract: This study have been conducted for evaluating agricultural practices and crop type effects on greenhouse gasses (GHG) emissions and soil carbon balance. Due to increase of GHGes in recent decades and their affect on Global warming, study of their emission from agricultural regions, seems to be necessary. The most important GHGes are carbon dioxide and methane. Carbon dioxide is increasing at the rate of 5% a year. Burning fuel and changing land use are two major human activities that result in this increase. Methane has a greenhouse effect as 21 times greater as CO2. At this study carbonic GHGes emissions from 3 fields were measured at Khuzestan Province in Iran. Experiment was conducted at 3 fields including rice-follow rotation (F1), follow-wheat rotation (F2) and melon-wheat rotation (F3); with 8 time sampling and with 3 repeats in completely randomized block design. Chamber method and gas chromatograph technique were used to measure CH4 and CO2 emission. Results showed that the highest amount of emission is related to CO2 and total emission is greatest for F1. This might be due to remaining crop residuals in this field and release of this gas during residuals decomposition. Average of methane emission was greatest for F1 (2.222 mg C m-2 day-1) and greatest emission was measured at near the rice harvest time on October, while the field 2 was a sink for atmospheric methane with mean of -0.106 (mg C m-2 day-1) and it was not significant difference with field 3 (zero). Methane emission from soils is depending on long paddy conditions at soil and these conditions are performing in rice cultivation.