Mealybugs (Hemiptera: Pseudococcidae) are major insect pests causing significant economic losses across diverse crops. This systematic review summarizes research on mealybugs, focusing on study types, species, host plants, and natural enemy groups in biological control, with emphasis on management-oriented literature to identify gaps in Integrated Pest Management (IPM). Literature searches in Scopus, PubMed, and Web of Science yielded 1,342 records, of which 56 peer-reviewed articles published between 2021 and 2025 met inclusion criteria through a PICOC-based screening. Research was geographically concentrated, with Brazil, Italy, the United States, and China as leading contributors. The 56 articles reported 35 mealybug species, highlighting a focus on biocontrol rather than global Pseudococcidae diversity. Phenacoccus solenopsis Tinsley, 1898 was the most studied species, and citrus and grapevine were the main host plants. Over half of the studies (53.6%) examined biological control, but research favored single-agent approaches: parasitoid-only studies (21.4%), predator-only and entomopathogen-only studies (10.7% each). Multi-agent systems were scarcely explored; six studies examined predator-parasitoid combinations, while only one investigated predator-entomopathogen interactions. Notably, no study examined three-agent systems. This gap is critical, as multi-agent outcomes are context-dependent, ranging from synergy to interference. The review identifies two key gaps: limited multi-agent experiments and absence of frameworks to manage their interactions. Addressing these gaps is essential to advance evidence-based, ecologically complex IPM strategies for mealybug management, emphasizing the need for research that evaluates multi-agent interactions and their practical implementation in pest management.