The objective of this study was to investigative the effects of amino acids supplementation on maturation, fertilization and embryo development of pig oocytes. Essential amino acids (EA), non-essential amino acids (NA) or both amino acids (EA + NA) were supple-mented to North Carolina State University (NCSU) 23 medium containing porcine follicular fluid (pFF). When the amino acids were supplemented to the maturation medium, the maturation rates were higher (p<0.05) in the NA group than control ($83.3{pm}0.04\%;versus;70.0{pm}0.05\%$, but the subsequent cleavage rates and development to morula and blstocyst stage between aminoacid supplement groups and control were not different. The developmental rates to morula and blastocysts stage were not significantly different regardless of amino acid supplementation to culture medium. In addition, supplementation of amino acids did not significantly affect the rate of fertilization and polyspermy. When the amino acids were supplement to culture medium, the number of trophectodermal (TE) cells was significantly (p<0.05) higher in amino acid supplement group than that of control ($18.6{pm}0.5;versus;16.1{pm}0.6$), whereas the numbers of inner cell mass (ICM) cells were not different among the treaonent groups and control ($29.0{pm}0.9~31.5{pm}1.2$). Total cell number was also significantly (p<0.05) higher in EANA group ($50.0{pm}1.0$) than that of control group ($44.2{pm}1.1$). These results indicate that the amino acid supplementation to maturation and culture medium may not significantly stimulate early embryo development, but may improve the TE cell number of blastocyst stage in the pig.