Lung　adenocarcinoma　(LADC)　exhibits　high　spatial　heterogeneity,　with　distinct　spatial　variations　in　pathological　features.　The　distribution　of　tertiary　lymphoid　structures　(TLS)　in　LADC　is　uneven,　and　different　TLS　characteristics　play　unique　roles.　To　investigate　the　correlation　between　TLS　features　and　other　pathological　characteristics,　particularly　tumor　spread　through　air　spaces　(STAS),　we　analyzed　TLS　and　other　pathological　features　on　whole-slide　images　stained　with　HE　and　CD20/CD23.　Additionally,　the　14-Gene　assay　was　used　to　assess　prognostic　risk.　Among　388　enrolled　LADC　patients,　226　(58.2%)　were　TLS-positive.　TLS　showed　a　negative　correlation　with　various　adverse　pathological　features,　with　boundary-area　TLS　demonstrating　the　strongest　correlation　with　STAS　quantity　(r=　-0.324,　P　＜　0.001).　Multivariate　Cox　analysis　identified　boundary-area　TLS　as　an　independent　prognostic　factor　for　recurrence-free　survival　(HR　=　0.856,　95%　CI　=　0.759–0.966,　P　=　0.026),　while　mature　TLS　was　an　independent　factor　for　overall　survival　(HR　=　0.841,　95%　CI　=　0.717–0.988,　P　=　0.035).　High-density　TLS　at　the　tumor　boundary　was　associated　with　low-risk　stratification　by　the　14-Gene　assay　(P　=　0.013).　This　study　highlights　the　negative　correlation　between　TLS　and　STAS,　especially　in　boundary　areas,　and　emphasizes　the　impact　of　tumor　microenvironment　spatial　characteristics　on　clinical　outcomes.　Assessment　of　spatial　heterogeneity　in　LADC　facilitates　precise　risk　stratification　for　patients.　©　The　Author(s)　2025.