Both Phones comes with a Metal build design and the Fingerprint Scanner on the front. OnePlus comes with a Dual Rear Camera Setup. On Display, OnePlus 5 has a .5-inch (1920×1080 pixels) Full HD Optic AMOLED 2.5D curved Corning Gorilla Glass 5 display whereas OnePlus 3T has a  5.5-inch (1920×1080 pixels) Full HD Optic AMOLED display with 2.5D curved Corning Gorilla Glass 4 protection.
OnePlus 5 is Powered by a 2.45GHz Octa-Core Snapdragon 835 64-bit 10nm processor whereas OnePlus 3T has a 2.35 GHz Quad-Core Snapdragon 821 processor.OnePlus comes with a 6/8GB LPDDR4x RAM and  64GB/128GB (UFS 2.1) internal storage compared to 6GB RAM and 64GB/128GB  internal storage on OnePlus 3T.
On Camera, OnePlus 5 has a Dual 16MP rear camera with dual LED Flash, Sony IMX398 sensor, f/1.7 aperture, 1.12μm pixel size, EIS + 20MP camera with f/2.6 aperture, Sony IMX350 sensor, 1.0μm pixel size, 4K at 30fps, 1080p at 60 fps, 720p slow motion at 120fps and 16MP front-facing camera with Sony IMX371 sensor, 1.0μm pixel size, f/2.0 aperture compared to 16MP rear camera with dual-tone LED Flash, Sony IMX298 sensor, PDAF, f/2.0 aperture and 16MP front camera on OnePlus 3T.Both Phones runs on Android 7.1.1 based on Oxygen OS and will get Android O Update.
OnePlus 3T is packed with 3400mAh Battery whereas OnePlus 5 has a 3300mAh Battery both supports Dash charge. OnePlus 5 is 7.25mm thin which is the slimmest OnePlus flagship ever and weight 153g.
OnePlus 5 vs OnePlus 3T
| Display: 5.5-inch (1920×1080 pixels) Full HD Optic AMOLED 2.5D curved Corning Gorilla Glass 5 display, sRGB, DCI-P3 color coverage |  5.5-inch (1920×1080 pixels) Full HD Optic AMOLED display with 2.5D curved Corning Gorilla Glass 4 protection |
| CPU:2.45GHz Octa-Core Snapdragon 835 64-bit 10nm processor | Â 2.35 GHz Quad-Core Snapdragon 821 processor |
| Adreno 540 GPU | Adreno 530 GPU |
| RAM 6GB LPDDR4x RAM, 8GB LPDDR4x RAM | Â 6GB RAM |
| ROM Â 64GB/128GB (UFS 2.1) internal storage | 64GB/128GB Â internal storage |
| Camera 16MP rear camera with dual LED Flash, f/1.7 aperture, 1.12μm pixel size + 20MP camera with f/2.6 aperture, 4K at 30fps slow motion at 120fps | 16MP rear camera with dual-tone LED Flash, Sony IMX298 sensor, PDAF, f/2.0 aperture |
| 16MP front-facing camera with Sony IMX371 sensor, 1.0μm pixel size, f/2.0 aperture | 16 MP front-facing camera |
| Dual SIM,4G VoLTE, WiFi 802.11ac dual-band (2×2 MU-MIMO ), Bluetooth 5.0 aptX HD, GPS/GLONASS/Beidou, USB Type-C, NFC | 4G with VoLTE, WiFi 802.11 a/b/g/n/ac (2.4/5 GHz), Bluetooth 4.1, GPS, USB 3.0 Type-C |
| Â Fingerprint Sensor | Fingerprint scanner |
| Battery 3300mAh battery with  Dash charge |  3400mAh battery with  Dash charge |
| OS-Android 7.1.1 (Nougat) with Oxygen OS | Android 7.1.1 with Oxygen OS |
| Dimensions: 154.2×74.1×7.25mm; Weight: 153g | Dimensions: 152.7×74.7×7.35mm; Weight: 158g |
OnePlus 5 comes in Midnight Black and Slate Gray color priced at $479 in the US and €499 in Europe for 6GB RAM model and will be officially available from June 27.India launch on June 22 expected to be priced at Rs 32999 whereas OnePlus 3T is priced at Rs 29,999 for 64GB and Rs 34999 for 128GB model.OnePlus 5 offers Faster Processor , Improved camera and Design similar to Apple iPhone 7 Plus.