Several selection methods for positive recombinant baculoviruses havebeen developed in the past years. The traditional plaque morphology difference method has been and will be replaced gradually by new methods based on drug resistance,antibiotic resistance etc,Some methods allow the homologous recombination process to be taken place in E.coli,in Saccharomyces cercoisiae or even in vitro. Owing to the greatly increasing frequency of positive recombinant virus,the stocks of positive recombinant virus are obtained easily. The advantages and disadvantages of each method are discussed.