Background: Psoriasis is a chronic lifelong skin disease most commonly causing erythematous popular and scaly plaques depending on lesion type. Secondary bacterial invaders complicate such lesions. Objectives of this study were to detect the types of aerobic and anaerobic bacterial invaders commonly complicate psoriatic lesions. Patients and Methods: Swabs were taken from different lesions of different sites of patients with psoriasis. Specimens were examined bacteriologically as soon as possible (within one hour) by direct gram stained smears were examined microscopically and indirectly by cultivation aerobically and anaerobic using suitable culture media and cultivation environments. Bacterial isolates were diagnosed and confirmed using suitable diagnostic techniques. Results: Psoriasis was found higher in individuals of age group (18-40) years old and majority of them (38; 48.7%) were showing distributed psoriatic lesions whole over the body. Staphylococcus aureus took the first rank of isolation 23 (29.5%). Proteus spp. and Staphylococcus epidermidis became next 11 and 9 for each respectively. Other bacterial isolates were showed lower rate of isolation like Pseudomonas aeruginosa, Bacillus spp. Enteric bacteria were primarily isolated from children. Also, E. coli and Enterococcus fecalis. Anaerobic bacteria represented by Propionobacter spp., Fusarium spp. and Clostridium perfringens were isolated within few numbers (3, 2, 1) for each respectively. Conclusion: Secondary bacterial infections of different types complicate psoriatic lesions on different sites of the body, so we recommended the follow up of perfect sanitation and disinfection with suitable antimicrobial regimen to reduce infection hazards.