This paper gives out another proof for Tychonoff Theorem. In proof，we based on Zorn's lemma，make use of that any net there is a cluster point，that is one of the equivalent propesitions of compact space，First，we lead in a concept of univesal net，and give out an example for it. Then，we proved a few properties of universal net (That is lemma 1，2，3, 4,). At the end，we proved Tychonoff Theorem，a famous theorem in general topology.