In some cases, an MRI exam have difficulty distinguishing fat and soft tissue around. Fat is often a source of problems in MRI, because fat around many anatomical structures, but not well constrained. Spair and Fatsat is a technique used to suppress the fat signal. Signal To Noise Ratio (SNR) is an influential factor in a lot of quality MRI image. This study aims to determine the difference in value SNR between sequences PDW_SPAIR and PDW_Fatsat MRI Knee Joint Pieces Sagittal. This research is a quantitative study with an experimental approach. Data were collected from November to December 2016 at the Radiology Siloam Hospital Lippo Village. Data taken from the examination using MRI Knee Joint PDW_SPAIR sequences and PDW_Fatsat on 10 probandus. Data was analyzed using software measurement ROI (Region Of Interest) in the organs of articular cartilage, anterior cruciate ligament, posterior cruciate ligament and Meniscus. then calculated the value of SNR, SNR values are tested with Shapiro Wilk normality test and showed normal distribution of data is then performed statistical tests using paired T test to determine whether or not there is a difference of the two sequences. Research show that there are differences between the sequences PDW_SPAIR SNR with PDW_Fatsat MRI Knee joint with a p value of 0.000 (p <0.05). When viewed from the mean value of the sequence PDW_SPAIR MRI Knee joint sagittal slice generate value SNR better than PDW_Fatsat sequences with a mean of 42.10 PDW_SPAIR and a mean value of 35.14 PDW_Fatsat. There is a difference Signal to Noise Ratio (SNR) between PDW_SPAIR (Spectral Adiabatic Inversion Recovery) sequence with PDW_Fatsat (Fat Saturation) sequence in examination of MRI Knee Joint Sagital Pieces with a significance level of p-value 0,000 (p<0,05). PDW_SPAIR sequence is an optimal value for Signal to Noise Ratio (SNR)in examination of MRI Knee Joint sagital pieces.