| Name | Code | Last | Cur | M. cap. | Industry |
|---|
| Okamoto Industries Inc | 5122 XJPX | 5,240.00 | JPY | 568 | Commodity Chemicals |
| Okamoto Machine Tool Works Ltd | 6125 XJPX | 3,835.00 | JPY | 159 | Industrial Machinery & Equipment |
| Okamura Corp | 7994 XJPX | 1,950.00 | JPY | 1,164 | Business Support Supplies |
| Okamura Foods Co Ltd | 2938 XJPX | 2,102.00 | JPY | 110 | Food Processing |
| Okano Valve Mfg. Co Ltd | 6492 XJPX | 5,400.00 | JPY | 55 | Industrial Machinery & Equipment |
| Okasan Securities Group Inc | 8609 XJPX | 626.00 | JPY | 779 | Investment Banking & Brokerage Services |
| Okato Holdings | 8705 XJPX | 185.00 | JPY | 66 | Investment Banking & Brokerage Services |
| Okaya Electric Industries Co Ltd | 6926 XJPX | 219.00 | JPY | 31 | Electrical Equipment |
| Okayamaken Freight Transportation Co Ltd | 9063 XJPX | 2,911.00 | JPY | 37 | Courier, Postal, Air Freight & Land-based Logistics |
| Okayama Paper Industries Co Ltd | 3892 XJPX | 1,228.00 | JPY | 35 | Paper Products |
| Oki Electric Industry Co Ltd | 6703 XJPX | 976.00 | JPY | 536 | Networking & Communications |
| Okinawa Cellular Telephone Co | 9436 XJPX | 4,225.00 | JPY | 1,304 | Wifi |
| Okinawa Electric Power Co Inc | 9511 XJPX | 905.00 | JPY | 312 | Electric Utilities |
| Okinawa financial Group Inc | 7350 XJPX | 2,526.00 | JPY | 342 | Banks |
| Okuma Corp | 6103 XJPX | 3,545.00 | JPY | 1,355 | Industrial Machinery & Equipment |
| Okumura Corp | 1833 XJPX | 3,795.00 | JPY | 888 | Engineering & Construction |
| Okumura Engineering Corp | 6229 XJPX | 1,252.00 | JPY | 35 | Industrial Machinery & Equipment |
| Okura Industrial Co Ltd | 4221 XJPX | 3,035.00 | JPY | 226 | Containers & Packaging |
| Okuwa Co Ltd | 8217 XJPX | 774.00 | JPY | 202 | Food Retail & Distribution |
| OLBA Healthcare Holdings Inc | 2689 XJPX | 1,955.00 | JPY | 73 | Medical Equipment |
| Olympic Group Corp | 8289 XJPX | 459.00 | JPY | 67 | Food Retail & Distribution |
| Olympus Corp | 7733 XJPX | 2,299.50 | JPY | 16,764 | Medical Equipment |
| OM2 Network Co Ltd | 7614 XJPX | 1,420.00 | JPY | 61 | Food Retail & Distribution |
| Omikenshi Co Ltd | 3111 XJPX | 291.00 | JPY | 12 | Textile & Leather |
| Omron Corp | 6645 XJPX | 5,055.00 | JPY | 6,138 | Electrical Equipment |
| Onamba Co Ltd | 5816 XJPX | 999.00 | JPY | 77 | Electrical Equipment |
| Oncolys Biopharma Inc | 4588 XJPX | 508.00 | JPY | 81 | Pharmaceuticals |
| OncoTherapy Science Inc | 4564 XJPX | 23.00 | JPY | 39 | Biotechnology |
| Ondeck Co Ltd | 7360 XJPX | 977.00 | JPY | 18 | Investment Banking & Brokerage Services |
| One Career Inc | 4377 XJPX | 4,370.00 | JPY | 165 | Online Services |
| One REIT Inc | 3290 XJPX | 233,100.00 | JPY | 403 | Other REITs |
| Onex Corp | 5987 XJPX | 2,101.00 | JPY | 22 | Iron & Steel |
| Onoken Co Ltd | 7414 XJPX | 1,520.00 | JPY | 242 | Iron & Steel |
| Ono Pharmaceutical Co Ltd | 4528 XJPX | 1,614.50 | JPY | 4,866 | Pharmaceuticals |
| Ono Sokki Co Ltd | 6858 XJPX | 537.00 | JPY | 34 | Industrial Machinery & Equipment |
| Ontsu Co Ltd | 7647 XJPX | 33.00 | JPY | 42 | Food Retail & Distribution |
| Onward Holdings Co Ltd | 8016 XJPX | 606.00 | JPY | 524 | Apparel |
| Ooedo Onsen Reit Investment Corp | 3472 XJPX | 64,200.00 | JPY | 127 | Hospitality REITs |
| Ookabe Glass Co Ltd | 5886 XJPX | 430.00 | JPY | 6 | Home Furnishings |
| Oomitsu Co Ltd | 3160 XJPX | 571.00 | JPY | 53 | Food Retail & Distribution |
| Ootoya Holdings Co Ltd | 2705 XJPX | 5,070.00 | JPY | 233 | Restaurants |
| Open Door Inc | 3926 XJPX | 584.00 | JPY | 114 | Online Services |
| Open House Group Co Ltd | 3288 XJPX | 5,148.00 | JPY | 3,813 | Other REITs |
| Open Up Group Inc | 2154 XJPX | 1,807.00 | JPY | 986 | Employment Services |
| OpenWork Inc | 5139 XJPX | 718.00 | JPY | 24 | Online Services |
| Optex Group Co Ltd | 6914 XJPX | 1,666.00 | JPY | 373 | Electrical Equipment |
| OPTiM Corp | 3694 XJPX | 660.00 | JPY | 232 | Software |
| Optimus Group Co Ltd | 9268 XJPX | 368.00 | JPY | 31 | Car retailers |
| OptoElectronics Co Ltd | 6664 XJPX | 230.00 | JPY | 8 | Office Equipment |
| Optorun Co Ltd | 6235 XJPX | 1,733.00 | JPY | 482 | Electronic Equipment |