Sexed semen technology is an efficient tool to produce more replacement heifers. How to use this technology is different depending on management and economic conditions. The objectives of this study were to explore the reproduction consequences of sex-sorted semen on sex ratio, conception rate and reproductive disorders (dystocia, abortion, stillbirth incedences) in heifers and first parity cows and to propose a bio-economic model for a cost-benefit analysis of sexed semen under Iranian production system. To do this, reproduction performances collected during 2006 to 2013 from 4 large dairy herds in Isfahan province of Iran were used and analyzed by GENMOD procedure of SAS software. Economics data for a cost-benefit analysis of different cenarios were gathere dusing questionnaires across investigated farms. The analysis were included the economic value (EV) when sexed semen is used in 1, 2 and 3 consecutive services, were compared with use conventional unsexed semen for all insemination. Rate of female born of sexed semen (86.3 %) was 1.8 times higher than those of conventional semen (48.5%). Sexed semen usages generally decreased conception rate so that the its average on the three first insemination in heifers reduced from 61.0% to 47.2% (P 0.001) while for first parity cows a reduction of 3.6% (from 33.8% to 30.2%) was not significant (P 0.05). stillbirth rate in heifers inseminated with sexed semen was upper than those of conventional semen (P=0.09). But there was no significant difference in the incidence of stillbirth between the two group of semen in cows (P 0.05). Use of sexed semen was significantly decreased the incidence of dystocia only in heifers (from 20.3% to 16.8%). There was no significant difference in abortion incidence between two groups of semen neither in heifers nor in cows. Scenarios with sexed semen had net present value (NPV) lower than the control program. The EV from the implementation of the first to third scenarios was estimated to be - 878,400, -1,454,500 and -1,818,700 Rials, respectively. Most economic losses were associated to age at first calving that was increased by reduction in conception rate of sexed semen. Heifer value and expected sexed semen conception rate as a percentage of the conventional conception rate, respectively were the most important economic and biological factors influencing the economic value of sexed semen. The obtained resultsin the study can be useful in cost-benefit analysis of sexed semen, under differente conomic and management conditions of Iran. Keywords : sexed semen, reproduction consequences, bio-economic model, net present value and economic value.