Objectives and Rationale Pseudococcus viburni Signoret (Hemiptera: Pseudococcidae), the obscure mealybug, is a serious polyphagous, cosmopolitan agricultural insect pest affecting deciduous production in South Africa. The presence of the mealybug in orchards result in significant damages to crops, with economic implications. The objective of the study was to assess the potential use of two entomopathogens, viz. entomopathogenic fungi (EPF) and nematodes (EPNs), as biological control agents against P. viburni under laboratory conditions, using screening bioassays. Methods Screening bioassays testing the pathogenicity of EPF against P. viburni, were conducted using eight local EPF isolates and one commercial Beauveria bassiana isolate (Broadband®). The pathogenicity of EPNs against the obscure mealybug was also tested using six In-vivo and two In-vitro cultured EPNs in screening bioassays. Key Results The results showed two EPF isolates, Metarhizium robertsii and M. pinghaense, as effective isolates against the mealybug, causing 96 % and 91 % mortality respectively, seven days post inoculation, incubated at 25 ºC. Applied at a concentration of 200 infective juveniles per insect, Heterorhabditis indica was the most effective EPN isolate against P. viburni, causing 79 % mortality, 48 h post inoculation (at 25 ºC). Further bioassays showed a positive correlation between EPF concentration and the time of exposure, with increase in conidial concentration, insect mortality increased over time. Conclusion and Discussion This study represents the first report on using multiple EPF isolates to control P. viburni and testing the infection potential of a South African isolate of H. indica. All milestones scheduled for this stage have been completed. .