The present study was to evaluate changes in microbial, TVB-N (volatile nitrogen bands), sensory evaluation and also the freshness index of carp (Ctenopharyngodon idella) fillet packed in at fillet packed in modified atmosphere (CO2 55% + N2 45%). . Microbial load parameter changes (national standard no. 2325), TVB-N (quasi-quantitative method), recently (K-value which includes the TP + ADP + AMP + IMP + HX + HXR) and its related psychological indicators (chromatographic HPLC machine) were investigated. The quality of the grass-fiber fillet packed in modified atmosphere showed a significant difference in time and temperature (p < 0.05) and with increasing time from 5 to 15 days and from 0 to 12 °C, these parameters showed an incremental (p < 0.05). Two indicators IMP and temperature decrease with increasing time and HxR (p < 0.05) and the lowest value on the day 15 and the temperature of 12 °C (p < 0.05). Grass Carp fillet was favorable at 0 ° C until the 15 day and at 6 ° C until 5 day, based on microbial indices, volatile nitrogen beds and novelty index for human consumption, but based on these indices at 12 ° C on days 5, 10 and 12 it was in unfavorable conditions. Temperature and time had a significant effect on all measured indices (p <0.01). Regarding the F-value, in all indices temperature was more effective than index time. The suggested formulas for all the indices studied in the experiment (dependent variables), had a correlation coefficient (R2) and modified explanatory coefficient (R2 -adj) close to 1. The proposed formulas for each indicator were able to predict the quality changes of Chenopharyngodon idella fillet packed in modified atmosphere with low error explanatory coefficient (R2 -adj) close to 1.