Tuta absoluta resistance to insecticides has become a dangerous problem in many tomato production areas in Egypt. We investigated the level of resistance to some insecticides currently used (λ- cyhalothrin, chlorpyrifos and imidaclopride)and recommended (chlorantraniliprole, emamectin benzoate, spinosad and indoxacarb) against T. absoluta which collected from two different localities, El- Salhia (Sami Saad Region, SSR) and (Abo Kabeer Region, AKR) at Sharkia governorate. Some biological aspects accompanied the tested insecticides resistance in field populations (SSR) in comparison with the laboratory reference strain (LRS) were studied. Also, the residues of λ- cyhalothrin in tomato fruits were determined. The results showed significant differences in the tolerance and/ or resistance levels to the tested insecticides among the two field populations of T. absoluta. The data showed that the resistance to certain insecticides namely chlorpyrifos, spinosad and lambda- cyhalothrin led to deleterious effects on some biological aspects (number of laid eggs/ female and total larval periods) in insecticides resistant field population (SSR) compared with LRS. Residues and dissipation of λ-cyhalothrin in tomato fruits were quantified at different harvest intervals of (2h), 1, 3, 5, 7, 9, 11, 13 and 15 days after insecticide application. Persistence, dissipation, half-life value and safe harvest interval of the insecticide in tomato were calculated. Results revealed that loss percentages of initial deposits in tomato fruits was 0.180 mg/ kg. and the half-life (t½) values were 1.004 day in tomato fruits. Data indicated that tomato fruits could be consumed safely after 3 days of treatment with λ-cyhalothrin.