||Dodders (Cuscuta spp., Convolvulaceae) are worldwide distributed parasites. A dodder often simultaneously parasitizes two or multiple adjacent hosts, forming dodder-connected plant clusters. Nitrogen (N) deficiency is a common challenge to plants. It is unclear whether dodder transfers N systemic signals between hosts grown in N-heterogenousheterogeneous soil. Transcriptome and methylome analyses were carried out to study whether dodder (Cuscuta campestris) transfers N-systemic signals between N-replete and N-deplete cucumber hosts, and it was found that N-systemic signals from the N-deficient cucumber plants were rapidly translocated through dodder to the N-replete cucumber plants, and unexpectedly, certain systemic signals were also transferred from the N-replete to N-deplete cucumber hosts. We demonstrate that these systemic signals were able to regulate large transcriptome and DNA methylome changes in the recipient hosts. Importantly, N stress also induced many long-distance mobile mRNAs between dodder and hosts and the bilateral N systemic signaling between N-replete and N-deplete hosts had a strongly impact on the inter-plant mobile mRNAs.15N labeling experiment indicated that under N heterogenousheterogeneous conditions, N systemic signals from the N-deficient cucumber hosts did not obviously change the N uptake activity of the N-replete cucumber hosts; however, in plant clusters composed of dodder-connected cucumber and soybean plants, when soybean plants were treated with N starvation, the cucumber plants exhibited increased N uptake activity. This study reveals a role of dodder in facilitating plant-plant communications under N-stress conditions by enabling extensive bilateral N-systemic signaling between different hosts.