Intersection checking of production rules in regular tree grammar is needed in XML type checking based on regular tree grammar with disjoint production rules.An algorithm is described,which checks the intersection between two automata according to the composition of the production rules in regular tree grammar.Firstly the automaton is constructed according to the content model of production rules,which is a regular expression,then it checks the intersection of the two automaton is constructed.The time complexity is O(‖E_1‖·‖E_2‖·|_(E1)_(E2)|).The experiment shows that this algorithm is sound and efficient.It is used in XML type checking based on regular tree grammar with disjoint production rules.