The objective of this study was to evaluate the effect of changes in seminal pH value at insemination on sex ratio of bovine embryos and confirm embryo sexing using Polymerase Chain Reaction (PCR). Eighteen Friesian cows superovulated with 2500 IU of PMSG and divided into three groups were used in this study. Cows in the first (G1), second (G2) and third (G3) group were artificially inseminated by diluted semen with pH values of 6.9 (control), 5.4 (acidic) and 8.4 (alkaline), respectively. Results showed insignificant (P≥0.05) effect of seminal pH value on ovulatory response and quality of recovered embryos. Change of seminal pH value to acidosis in (G2) produced higher (P<0.01) number of females (19/32, 59.4%) than males (13/32, 40.6%). Change of seminal pH value to alkaline (G3) produced higher (P<0.01) number of males (61.8%) than females (38.2%). However, sex ratio of cows inseminated with control semen (pH=6.9, G1) was 51.9% males: 48.2% females. In conclusion, change of seminal pH value to alkaline tended to produce more males, while acidic semen tended to produce more females. Based on these results motility of spermatozoa bearing Y-chromosome may be affected by the acidic condition of the semen, while X-chromosome had an opposite trend.