National Route 146
国道146号
Japan Romantic Road
Route 146 in Karuizawa
Route information
Length	30.2 km[1] (18.8 mi)
Existed	1953–present
Major junctions
South end	National Route 18 in Karuizawa, Nagano
North end	National Route 144 / National Route 145 in Naganohara, Gunma
Location
Country	Japan
Highway system
National highways of Japan Expressways of Japan
← National Route 145 → National Route 147

National Route 146 is a national highway of Japan connecting Naganohara, Gunma and Karuizawa, Nagano in Japan, with a total length of 30.2 km (18.77 mi).