diff --git a/models/repo.go b/models/repo.go
index fd2e75a0e..bf7bf018a 100644
--- a/models/repo.go
+++ b/models/repo.go
@@ -1454,7 +1454,7 @@ func updateRepository(e Engine, repo *Repository, visibilityChanged bool) (err e
 			return fmt.Errorf("getRepositoriesByForkID: %v", err)
 		}
 		for i := range forkRepos {
-			forkRepos[i].IsPrivate = repo.IsPrivate
+			forkRepos[i].IsPrivate = repo.IsPrivate || repo.Owner.Visibility == api.VisibleTypePrivate
 			if err = updateRepository(e, forkRepos[i], true); err != nil {
 				return fmt.Errorf("updateRepository[%d]: %v", forkRepos[i].ID, err)
 			}
diff --git a/modules/repository/fork.go b/modules/repository/fork.go
index 2ed2a0eb7..169c391ed 100644
--- a/modules/repository/fork.go
+++ b/modules/repository/fork.go
@@ -12,6 +12,7 @@ import (
 	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/structs"
 )
 
 // ForkRepository forks a repository
@@ -36,7 +37,7 @@ func ForkRepository(doer, owner *models.User, oldRepo *models.Repository, name,
 		LowerName:     strings.ToLower(name),
 		Description:   desc,
 		DefaultBranch: oldRepo.DefaultBranch,
-		IsPrivate:     oldRepo.IsPrivate,
+		IsPrivate:     oldRepo.IsPrivate || oldRepo.Owner.Visibility == structs.VisibleTypePrivate,
 		IsEmpty:       oldRepo.IsEmpty,
 		IsFork:        true,
 		ForkID:        oldRepo.ID,
diff --git a/routers/org/setting.go b/routers/org/setting.go
index 348d8cc8d..79a99295a 100644
--- a/routers/org/setting.go
+++ b/routers/org/setting.go
@@ -85,12 +85,30 @@ func SettingsPost(ctx *context.Context, form auth.UpdateOrgSettingForm) {
 	org.Description = form.Description
 	org.Website = form.Website
 	org.Location = form.Location
-	org.Visibility = form.Visibility
 	org.RepoAdminChangeTeamAccess = form.RepoAdminChangeTeamAccess
+
+	visibilityChanged := form.Visibility != org.Visibility
+	org.Visibility = form.Visibility
+
 	if err := models.UpdateUser(org); err != nil {
 		ctx.ServerError("UpdateUser", err)
 		return
 	}
+
+	// update forks visibility
+	if visibilityChanged {
+		if err := org.GetRepositories(models.ListOptions{Page: 1, PageSize: org.NumRepos}); err != nil {
+			ctx.ServerError("GetRepositories", err)
+			return
+		}
+		for _, repo := range org.Repos {
+			if err := models.UpdateRepository(repo, true); err != nil {
+				ctx.ServerError("UpdateRepository", err)
+				return
+			}
+		}
+	}
+
 	log.Trace("Organization setting updated: %s", org.Name)
 	ctx.Flash.Success(ctx.Tr("org.settings.update_setting_success"))
 	ctx.Redirect(ctx.Org.OrgLink + "/settings")
diff --git a/routers/repo/pull.go b/routers/repo/pull.go
index d4c99e276..30913e476 100644
--- a/routers/repo/pull.go
+++ b/routers/repo/pull.go
@@ -24,6 +24,7 @@ import (
 	"code.gitea.io/gitea/modules/notification"
 	"code.gitea.io/gitea/modules/repofiles"
 	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/structs"
 	"code.gitea.io/gitea/modules/util"
 	"code.gitea.io/gitea/routers/utils"
 	"code.gitea.io/gitea/services/gitdiff"
@@ -95,15 +96,16 @@ func getForkRepository(ctx *context.Context) *models.Repository {
 		return nil
 	}
 
-	ctx.Data["repo_name"] = forkRepo.Name
-	ctx.Data["description"] = forkRepo.Description
-	ctx.Data["IsPrivate"] = forkRepo.IsPrivate
-	canForkToUser := forkRepo.OwnerID != ctx.User.ID && !ctx.User.HasForkedRepo(forkRepo.ID)
-
 	if err := forkRepo.GetOwner(); err != nil {
 		ctx.ServerError("GetOwner", err)
 		return nil
 	}
+
+	ctx.Data["repo_name"] = forkRepo.Name
+	ctx.Data["description"] = forkRepo.Description
+	ctx.Data["IsPrivate"] = forkRepo.IsPrivate || forkRepo.Owner.Visibility == structs.VisibleTypePrivate
+	canForkToUser := forkRepo.OwnerID != ctx.User.ID && !ctx.User.HasForkedRepo(forkRepo.ID)
+
 	ctx.Data["ForkFrom"] = forkRepo.Owner.Name + "/" + forkRepo.Name
 	ctx.Data["ForkFromOwnerID"] = forkRepo.Owner.ID
 
diff --git a/routers/repo/setting.go b/routers/repo/setting.go
index dff13ff5b..1433bedb3 100644
--- a/routers/repo/setting.go
+++ b/routers/repo/setting.go
@@ -102,7 +102,7 @@ func SettingsPost(ctx *context.Context, form auth.RepoSettingForm) {
 
 		// Visibility of forked repository is forced sync with base repository.
 		if repo.IsFork {
-			form.Private = repo.BaseRepo.IsPrivate
+			form.Private = repo.BaseRepo.IsPrivate || repo.BaseRepo.Owner.Visibility == structs.VisibleTypePrivate
 		}
 
 		visibilityChanged := repo.IsPrivate != form.Private