Crystal structures have been refined from single-crystal X-ray diffraction data for eight synthetic (Li, Na)GaSi₂O₆ clinopyroxenes, crystallized at 1770 K/6 GPa or annealed at 573 k/l atm. The space group is C2/c and Z is 4. The structures of the lithium rich pyroxenes are similar to that of spodumene(LiA1Si₂O₆) and the structures of the sodium rich pyroxenes are similar to that of jadeite(NaA1Si₂O₆). Although the crystallographical Ga site is only one in the (Li, Na)GaSi₂O₆ pyroxene, the correlations between the mean <Ml-O1> distance and the M1-O2 distance and between the O1-Si-O2 angles and the differences, d_br-nbr (=mean <Si-O(br)>-mean <Si-O(nbr)>), where br denotes bridging and nbr nonbridging, suggest that there are two different electronic states for the octahedral Ga ions.