The function you need is beforeShowDay
here is an example which should work for you.
$('#datepicker_1').datepicker({
beforeShowDay: nonWorkingDates,
dateFormat: 'dd/mm/yy',
showAnim: 'show',
onClose: closeDatePicker_datepicker_1
});
function nonWorkingDates(date){
var day = date.getDay(), Sunday = 0, Monday = 1, Tuesday = 2, Wednesday = 3, Thursday = 4, Friday = 5, Saturday = 6;
var closedDays = [[Sunday],[Monday],[Wednesday],[Thursday],[Friday],[Saturday]];
for (var i = 0; i < closedDays.length; i++) {
if (day == closedDays[i][0]) {
return [false];
}
}
return [true];
}
code you need is in red.
For other days to exclude, such as national holidays, take a look at the original thread..
can-the-jquery-ui-datepicker-be-made-to-disable-saturdays-and-sundays-and-holid