PLATZ, a novel zinc finger DNA-binding protein, plays crucial regulatory roles in the growth and development of various plants and in the modulation of abiotic stress responses. However, knowledge of the functions of PLATZ genes in tomato (Solanum lycopersicum) is lacking. In our study, we established stable SlPLATZ17 gene overexpression and knockout lines to further analyze the regulatory functions of SlPLATZ17 under drought and salt stress. It was found that the overexpression lines presented increased drought and salt tolerance under stress. Transcriptome sequencing and screening for interacting proteins revealed that SlPLATZ17 may exert its effects by interacting with POR1, thereby influencing glutathione metabolism and arginine and proline metabolism. In conclusion, the findings lay the groundwork for a deeper understanding of the regulatory mechanisms underlying the role of SlPLATZ17 in stress resistance, as well as facilitating the application of SlPLATZ17 in the breeding of stress-resistant tomato varieties.