Yes....it's called flour!
Arrowroot is also used, or tapioca flour, but it gets disgusting and ropy upon reheating.
Linda C

Flour would be the alterntive, but keep in mind that it won't turn clear as cornstarch does when you use it for thickening. It won't give your oriental dishes that traditional sparkling clear look they get with cornstarch.

If using flour, remember it takes twice as much as you would use of cornstarch.

I also was going to suggest arrowroot. Here is good information that you may find helpful:

ARROWROOT AS A THICKENER

We couldn't ask for a better thickener. This silky white powder is a pure starch derived from a tropical American plant. It is fat-free, easy to digest and flavorless (so it won't interfere with the delicate sauces). It thickens at low temperature and is perfect for heat-sensitive egg-based sauces and custards. It has twice the thickening power of wheat flour and does not get cloudy upon thickening, so it makes beautiful fruit sauces and gravies. Moreover it has none of the chalky taste associated with cornstarch.

To store arrowroot, keep in an airtight container marked with the date that you bought it. Use within 2 months because its thickening properties diminish with age. When using arrowroot, dissolve 1 1/2 teaspoons arrowroot in 1 tablespoon cold liquid. Stir or whisk the cold mixture into 1 cup of hot liquid at the end of the cooking time. Stir until thickened which is about 5 seconds. These proportions will make about 1 cup of medium-thick sauce, soup or gravy. For thinner sauce, use 1 teaspoon arrowroot. For a thicker sauce, use up to 1 tablespoon arrowroot.

If you are using it to replace cornstarch, use 1 tablespoon arrowroot in place of 2 teaspoons cornstarch. While to replace flour, use half as much arrowroot as flour. If the recipe calls for 1 tablespoon flour, substitute 1 1/2 teaspoons arrowroot.

To keep an arrowroot-thickened sauce thick, just stir until just combined. Over-stirring can make it thin again.

Fascinating Fact :

The word arrowroot is believed to originate with Native Americans, who used the root to draw out poison from arrow wounds. Another possible origin is a Native American word for flour, araruta. Its scientific name is Maranta arundinacea.

Here are some notes I have in my file on thickeners...

-Grainlady

Wheat flour (all-purpose)
-Poor resistance to thinning when overcooked.
-Fair gel formation.
-Does not freeze well.

Cornstarch
-Good resistance to thinning when overcooked.
-Good gel formation.
-Does not freeze well.

Arrowroot
-Good resistance to thinning when overcooked.
-Fair gel formation.
-Does not reheat well.

Tapioca
-Fair-Poor resistance to thinning when overcooked.
-Poor gel formation.
-Freezes well.

Potato starch
-Fair resistance to thinning when overcooked.
-Poor gel formation

Rice flour
-Good resistance to thinning when overcooked.
-Poor gel formation.
-Freezes well.

Substitutions for Thickeners -

For every 2 T. of flour, substitute:

4 T. browned flour
1 T. cornstarch
2-1/2 t. arrowroot
1 T. tapioca (quick cooking, granulated)
1 T. potato starch
2-1/2 t. rice flour or rice starch
(3 t. = 1 T.)